In a public-key cryptosystem, (71) encrypted with the public key can only be deciphered with the private key from the same (72) . Conversely, (71) encrypted with the private key can be decrypted only with the public key. Users can make their public keys (73) available or place them at a key distribution center or others to access. However, the private key must be (74) safe. In public-key systems there’s no (75) to find a safe channel for communicating a shared secret key.

A. length B. pair C. sizeD. space

企业为贡献突出的员工设立特别奖金，保证其收入水平不降低，以留住骨干员工，保持企业的竞争力。这反映了奖金计划的（）

A.激励性

B.兼容性

C.灵活性

D.可控性