[单选题]
An object in simple harmonic motion obek7+d( hqnkla, ys the following position:0 2 5wic rc1w.rfwiaoz+nn 9w versus time equation: 1f.r z29wwicwa0n:5ir+ ncwo $y = 0.50 \; \sin (\pi/2 \times t)$. What is the amplitude of vibration?
A. $0.25 \; m$
B. $0.50 \; m$
C. $0.75 \; m$
D. $1.0 \; m$
