Given the function $y=\cos\left(x+\frac{3\pi}{2}\right)$, identify the amplitude, period, and phase shift from the options below. Then, sketch its graph by considering only one period.

• A. $\text{Amplitude}=\frac{3}{2},~\text{Period}=2\pi,~\text{Phase shift}=-\frac{\pi}{2}$
• B. $\text{Amplitude}=\frac{3}{2},~\text{Period}=\pi,~\text{Phase shift}=\frac{\pi}{2}$
• C. $\text{Amplitude}=1,~\text{Period}=2\pi,~\text{Phase shift}=-\frac{3\pi}{2}$
• D. $\text{Amplitude}=1,~\text{Period}=2\pi,~\text{Phase shift}=\frac{3\pi}{2}$

Answer: (C)