问题 单项选择题

ISO定义了网络管理的五大功能,包括:故障管理、安全管理、计费管理、性能管理和()。SNMP是一个()的协议,其网络管理模型由()三部分构成。SNMP的命令有()和trap,其中trap操作用于()。

SNMP是一个()的协议

A.异步的请求/响应和无连接

B.同步的请求/响应和五连接

C.异步的请求/响应和面向连接

D.同步的请求/响应和面向连接

答案

参考答案:A

单项选择题
单项选择题

"In the long run," as John Maynard Keynes observed, "we are all dead. " True. But can the (1) run be elongated in a way that makes the long run (2) And if so, how, and at what cost People have dreamt of (3) since time immemorial. They have sought it since the first alchemist put an elixir of (4) on the same shopping list as a way to turn lead into gold. They have (5) about it in fiction, from Rider Haggard’s "She" to Frank Herbert’s "Dune". And now, with the growth of (6) knowledge that has marked the past few decades, a few researchers believe it might be within (7) .

To think about the question, it is important to understand why organisms-people (8) -age in the first place. People are like machines: they (9) That much is obvious. However, a machine can always be (10) A good mechanic with a stock of spare parts can keep it going (11) . Eventually, no part of the (12) may remain, but it still carries on, like Lincoln’s famous axe that had three new handles and two new blade.

The question, of course, is whether the machine is worth (13) . It is here that people and nature (14) . Or, to put it slightly (15) , two bits of nature disagree with each other. From the individual’s point of view, (16) is an imperative. You cannot reproduce unless you are alive. A fear of death is a sensible evolved response and, since (17) is a sure way of dying, it is no surprise that people want to stop it in its tracks. Moreover, even the appearance of ageing can be (18) . It (19) the range of potential sexual partners who find you attractive-since it is a sign that you are not going to be (20) all that long to help bring up baby-and thus, again, curbs your reproduction.

10()

A.disposed

B.repaired

C.bought

D.replaced