问题
单项选择题
Password is a secret series of (73) that enables a user to access a file, computer, or program. On multi-user systems, each user must enter his or her password before the computer will respond to (74) . The password helps ensure that (75) users do not access the computer. In addition, data files and programs may require a password.
A. symbolB. sign C. characters D. characteristic
答案
参考答案:D