安定无下列哪一特点( )。

A．口服安全范围较大
B．其作用是间接通过增加GABA实现
C．长期应用可产生耐受性
D．大剂量对呼吸中枢有抑制作用
E．为典型的药酶诱导剂

In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private-key encryption methods are called (71) ciphers, information is encrypted with (72) both the sender and receiver hold privately. Public-key encryption methods are called (73) ciphers, (74) created for each user, encryption key and deception key are (75)

A．synchronous

B．Asynchronous

C．symmetric

D．asymmetric