In order to cover his three sons expenses at college, Jack applied to a bank for a loan of

In order to cover his three sons expenses at college, Jack applied to a bank for a loan of 200 000 dollars. The bank approved of his application______his house is to be mortgaged if he cant pay off the loan before the deadline.

A．on condition that

B．in the event that

C．with the result that

D．by reason that

请帮忙给出正确答案和分析，谢谢！