A ball \(A\) is thrown horizontally, and at the same time, another ball \(B\) is thrown with an angle of \(\theta\) to the horizontal line, as shown above. The horizontal throw lengths of the two balls are the same, which is \(s\) in the picture, and the landing point of both balls is the point \(P\) on the floor. Until the ball \(A\) arrives at \(P,\) which of the following statements is correct?
a) The two balls arrive at \(P\) at the same time.
b) The accelerations of the two balls are the same.
c) The velocity of the ball \(B\) relative to that of the ball \(A\) is constant.