Two children, Bob and Mary, have piggy ban

题目：

Two children, Bob and Mary, have piggy banks into which they deposit money earned from doing odd jobs. In a certain year, both Bob and Mary each deposited $5 on the first of every month into their respective piggy banks. If these were the only deposits made into the piggy banks during the year, on December 31 does Bob have more money in his piggy bank than Mary has in her piggy bank (Assume no withdrawals)（）
(1)On March 15 Bob had three times as much money in his piggy bank as Mary had in hers.
(2)On June 15 Bob had twice as much money in his piggy bank as Mary had in hers.

A．条件(1)充分，但条件(2)不充分．

B．条件(2)充分，但条件(1)不充分．

C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．

D．条件(1)充分，条件(2)也充分．

E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．