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[主观题]

转基因作物目前在世界上已种植有1000万公顷左右,种植最多的是棉花、玉米和西红柿等。在实验室试种

的还有莴苣、西瓜、稻谷等品种。试验的目的除了增产之外,还在于提高这些品种的抗病毒能力。但同时也有专家担心转基因作物可能对环境有危险。比如在美国栽种的那种能抗虫害的玉米和棉花,可能加快一些更难对付的害虫的出现。这类作物的所有分子都分泌出一些微量的“杀虫药”,尤其是那些能抗除莠剂的作物,它们一旦同野生状态下的“表姐妹”杂交之后,那些“表姐妹”也就会因此而成为除莠剂无法除掉的变种了。 下列说法与原文意思相符的一项是:

A.转基因作物的研究已取得实质性进展。目前很多品种都得到推广种植

B.提高作物抗病毒的能力仍然是转基因作物技术研究没有完全解决的问题

C.更难对付的害虫的出现将是转基因作物给环境带来的最大危险

D.增产并不是转基因技术研究的主要目的,提高抗病毒能力是研究者最感兴趣的

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第1题

You have implemented mutua l route redistribution between OSPF and EIGRP on a border route
r. When checking the routing table on one of the EIGRP routers within the EIGRP routing domain, you are seeing some, but not all of the expected routes.What should you verify to troubleshoot this problem?()

A. The border router is using a proper seed metric for OSPF

B. The border router is using a proper seed metric for EIGRP

C. The administrative distance is set for OSPF and EIGRP

D. The missing OSPF routes are present in the routing table of the border router

E. The subnet keyword on the border router in the redistribute OSPF command

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第2题

Refer to the exhibit. Routers R1 and R2 have been configured to operate with OSPF. Routers
R1 and R3 have been configured to operate with RIP. After configuring the redistribution between OSPF a nd RIP on R1, no OSPF routes are distributed into RIP. What should be done to correct this problem? ()

A. The redistribution command should be reentered with the match route - type parameter included.

B. The redistribution command should be reentered wit h the route - map map - tag parameter included.

C. The redistribution command should be reentered with the metric metric - value parameter included.

D. Routes will first need to be distributed into another protocol, and then into RIP.

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第3题

You can successfully ping a Bridged 1483 customer‘s workstation from the local ERX. However, a remote ERX router in your network cannot ping that same device.What could be causing this problem?()

A. incorrect DSL network redistribution

B. incorrect static host route configuration

C. incorrect static customer route configuration

D. incorrect default static route configuration on the end user

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第4题

When implementing MPLS VPNs between CE and PE routers, which of these statements is correc
t?As a Network Engineer, it is necessary for you to know how to implement MPLS VPNs between Customer Edge and Provider Edge routers.Refer to the following descriptions, which one is making sense?()

A. If using OSPF or EIGRP as the PE-CE routing protocol, redistribution is not required, but any other protocol or static route will require redistribution

B. If using IS-IS as the PE-CE routing protocol, no redistribution is required

C. If using static routes between the CE and PE routers, no redistribution of other VPN routes is required

D. If PE-CE protocol is not BGP, redistribution of other VPN routes from MP-BGP is required

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第5题

You have been asked to create a static route with a next hop that is not directly connected to the router. Which configuration parameter enables the static route to accomplish this scenario?()

A.resolve

B. indirect

C. next-hop

D. recursive

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第6题

When implementing MPLS VPNs between CE and PE routers, which of these statements is correct? ()

A. If using IS-IS as the PE-CE routing protocol, no redistribution is required.

B. If using static routes between the CE and PE routers, no redistribution of other VPN routes is required.

C. If the PE-CE protocol is not BGP, redistribution of other VPN routes from MP-BGP is required.

D. If RIP is the routing protocol that is used between the PE-CE routers, no redistribution is required, but any other protocol will require redistribution.

E. If using OSPF or EIGRP as the PE-CE routing protocol, redistribution is not required, but any other protocol or static route will require redistribution.

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第7题

Refer to the exhibit. Which three statements accurately describe the result of applying the exhibited route map?()

A. The map prohibits th e redistribution of all type 2 external OSPF routes.

B. All routes that do no match clauses 10 and 20 of the route map are redistributed with their tags set to 8.

C. The map prohibits the redistribution of all external OSPF routes with tag 6 set.

D. Th e map permits the redistribution of all type 1 external OSPF routes.

E. The map redistributes into EIGRP all routes that match the pfx prefix list and the five metric values?0000, 1000, 255, 1, and 1500.

F. The map prohibits the redistribution of all ty pe 2 external OSPF routes with tag 6 set.

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第8题

You have received a default route through BGP from your ISP and you want to redistribute it into OSPF.Which method will accomplish this?()

A. Apply an export policy to OSPF that exports the default route

B. Apply an import policy to OSPF that imports the default route

C. Apply the default-network command to OSPF

D. Apply the redistribute-igp command to BGP

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第9题

You have received a default route through BGP from your ISP and you want to redistribute it into OSPF.Which mehtod will accomplish this?()

A. Apply an export policy to OSPF that exports the default route

B. Apply an import policy to OSPF that imports the default route

C. Apply the default-network command to OSPF

D. Apply the redistribute-igp command to BGP

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第10题

You have just configured a static default route on router TK1. What is the purpose of a default route?()

A. It is a route to be used when the routing protocol fails.

B. It is a route configured by an ISP that sends traffic into a corporate network.

C. It is a route used when a packet is destined for a remote network that is not listed in the routing table.

D. It is a route manually configured for a specific remote network for which a routing protocol is not configured.

E. It is used to send traffic to a stub network.

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