根据字母提示，补全对话。

Mom: What are you d____________?

Jack: I'm making a b____________ chart for our f____________. W____________ is your birthday?

Mom: It's in A____________.

Jack: My u____________ birthday is in A____________, too. When's my f____________ birthday?

Mom: It's in O____________. And your aunt's birthday is in F____________.

Jack: Great! Here's the chart.

债权人行使代位权的必要费用，由( )负担。

A．债权人负担

B．债务人负担

C．债权人和债务人协商负担

D．债权人和债务人协商平摊