Certificates are (66) documents attesting to the (67) of a public key to an individual or other entity. They allow verification of the claim that a given public key does in fact belong to a given individual. Certificates help prevent someone from using a phony key to (68) someone else. In their simplest form, Certificates contain a public key and a name. As commonly used, a certificate also contains an (69) date, the name, of the CA that issued the certificate, a serial number, and perhaps other information. Most importantly, it contains the digital (70) of the certificate issuer. The most widely accepted format for certificates is X.509, thus, Certificates can be read or written by any application complying with X.509.

A．signature

B．mark

C．stamp

D．hypertext

有关建筑涂料的说法不正确的是（）。

A.建筑涂料应向着减少污染、耐候性优异、功能复合化方向发展

B.建筑涂料向环保型、低毒型方向发展

C.建筑涂料要开发推广油性涂料系列

D.发展高性能外墙涂料生产技术，适应高层建筑外装饰的需求