From the diagram above, the bob of the pendulum has the fastest speed at
Attached Figure / Diagram
A
X
B
Y
C
Z
D
W
Verified Correct Answer: A.
Physical Principles & Numerical Solution
The ball has its fastest speed at its equilibrium position when its displacement X = 0, which is at X. At this point, the bob has maximum velocity and maximum kinetic energy.
Source: Myschool Past Questions Archive (Record #14382)