Let's solve the equation step-by-step.
The equation given is:
\[ -(3y + 9) - (-2y + 2) = -6 \]
First, distribute the negative signs:
\[ -3y - 9 + 2y - 2 = -6 \]
Now, combine like terms:
\[ (-3y + 2y) + (-9 - 2) = -6 \]
This simplifies to:
\[ -y - 11 = -6 \]
Next, isolate \(y\) by adding 11 to both sides:
\[ -y = -6 + 11 \]
This simplifies to:
\[ -y = 5 \]
Now, multiply both sides by -1:
\[ y = -5 \]
Thus, the solution to the equation is:
\[ \boxed{-5} \]
The correct answer is C. \(-5\).