单项选择题
A．POP3 B．SMTP C．IMAP D．MPLS
A．＜a href="email:test@test.com"＞test@test.com＜/a＞ B．＜a href="emailto:test@test.com"＞test@test.com＜/a＞ C．＜a href="mail:test@test.com"＞test@test.com＜/a＞ D．＜a href="mailto:test@test.com"＞test@test.com＜/a＞
A．READ B．GET C．HEAD D．POST