Starting at time t = 0 from the origin with speed 1 ms, a particle follows a two-dimensional trajectory in the x-y plane so that its coordinates are related by the equation y=- The x and y components of its 2 acceleration are denoted by a, and ay, respectively. Then (A) ax = 1 ms implies that when the particle is at the origin, ay = 1 ms (B) ax = 0 implies ay = 1 ms at all times (C) at t=0, the particle's velocity points in the x-direction (D) ax = 0 implies that at t = 1 s, the angle between the particle's velocity and the x axis is 45