If a certificate authority trustpoint is not configured when enabling HTTPS and the remote HTTPS server requires client authentication，connections to the secure HTTP client will fail. Which command must be enabled for correct operation？（）

A.ip http client secure-ciphersuite 3des-ede-cbc-sha
B.ip https max-connections 10
C.ip http timeout-policy idle 30 life 120 requests 100
D.ip http client secure-trustpoint trustpoint-name