Step 1: Concept
SHM kinematics and graphical representation.
Step 2: Analysis
* Statement I: Velocity $v = \omega \sqrt{A^2 - x^2}$. Squaring gives $v^2/\omega^2 + x^2 = A^2$, which is an ellipse, not a parabola.
* Statement II: $v = A\omega \cos(\omega t)$, which is sinusoidal.
* Statement III: $v = A\omega \cos(\omega t)$ and $a = -A\omega^2 \sin(\omega t)$. Since $\sin^2\theta + \cos^2\theta = 1$, $(v/A\omega)^2 + (a/A\omega^2)^2 = 1$, which is an ellipse.
Step 3: Conclusion
Statements II and III are correct.
Final Answer: (B)