多选题For which three events can web application event listeners be registered？ （）Awhen a session is createdBafter a servlet is destroyedCwhen a session has timed outDwhen a cookie has been createdEwhen a servlet has forwarded a requestFwhen a session attrib
题目
多选题
For which three events can web application event listeners be registered？ （）
A
when a session is created
B
after a servlet is destroyed
C
when a session has timed out
D
when a cookie has been created
E
when a servlet has forwarded a request
F
when a session attribute value is changed