To evaluate the expression \(-3 - (-6)\), we can use the concept of the additive inverse. The additive inverse of a number \(x\) is \(-x\), and subtracting a negative number is the same as adding its positive.
So, we can rewrite the expression as:
\[ -3 - (-6) = -3 + 6 \]
Now, we can evaluate \(-3 + 6\):
\[-3 + 6 = 3\]
Thus, the answer to the original problem is 3.
Looking at the options provided, the correct response is:
"Because -3 + 6 is an equivalent expression, the answer is 3."