根据对话内容，从方框中选择恰当的选项补全对话。
A：Hey，Betty.At eight o'clock last night you weren't at home，were you?
B：No.______
A：Well，I called you at eight o'clock but no one answered.Where were you?
B：______
A：What were you doing there at that time?
B：______What did you call for?  
A：______
B: Did you work it out at last?    
A：Yes，I did.
B：______
A：Your good friend Alan.
B：Oh，Alan is better at math than me.

A．I was having a party for Linda.    B．What's wrong? C．I wanted you to help me work out a math problem. D．I was at Linda's home.    E．Who helped you?