[单选题]
Ball A is dropped from t:3 cb* p:,aexyxdk. phshzc27)x)0xjaep / 0vm d )pjmhe top of a building. One second later, ball B is dropped from the same building. As t)m)e xa/p 0x cjh0v )mdj2spz7ime progresses, the difference in their speeds
A. increases.
B. remains constant.
C. decreases.
D. cannot be determined from the information given.
