[单选题]
An object in simple harmonic motion obeys the 0f7v qkjliyv)-zk b;3following position versus timj k 1(f:wz6trhepa0e:1hvd s0e equation:ehf1p01 (de jvr k0a :hz:6tsw $y = 0.50 \; \sin (\pi/2 \times t)$. What is the amplitude of vibration?
A. $0.25 \; m$
B. $0.50 \; m$
C. $0.75 \; m$
D. $1.0 \; m$
