The called party can ring but does not show the caller number. What are the possible reasons? (Multiple Choice)

The called party can ring but does not show the caller number. What are the possible reasons? (Multiple Choice)
A . The softswitch does not configure caller ID
B . AG did not receive caller information from Softswitch
C . The environment of the equipment room is not good, for example, the equipment and the distribution frame are not well grounded
D . The user’s phone does not support caller ID

Answer: ABCD