The problem involves using the unit circle and trigonometric functions to evaluate values for $s = -\pi$, and the question is asking for the value of $\sin(-\pi)$.

Step-by-step Solution:

1. Understanding the Unit Circle:

   • On the unit circle, the sine of an angle corresponds to the y-coordinate of the point where the terminal side of the angle intersects the circle.
   • The angle $\pi$ radians is equivalent to 180°, which corresponds to the point $(-1, 0)$ on the unit circle.

2. Sine Function:

   • $\sin(\theta)$ is the y-coordinate of the point on the unit circle.
   • Since $\pi$ corresponds to the point $(-1, 0)$, the sine of $\pi$ is 0.

3. Negative Angles:

   • For $\sin(-\theta)$, we reflect the point across the x-axis. For $\theta = \pi$, the reflection across the x-axis is still at $( -1, 0 )$.
   • Therefore, $\sin(-\pi) = 0$.

Conclusion:

The value of $\sin(-\pi)$ is 0, so the correct answer is: $A: \sin(-\pi) = 0$

Would you like further details, or do you have any questions about this? Here are five related questions to explore further:

1. What is the cosine value for $\cos(-\pi)$?
2. How do we compute $\tan(-\pi)$ using the unit circle?
3. What is the general property of sine and cosine for negative angles?
4. Why does the unit circle have a radius of 1?
5. How can we find the sine of any angle greater than $2\pi$?

Tip: Always visualize the angle on the unit circle to understand the behavior of trigonometric functions better.