Let's solve the equation step by step:
Given: \[ -5(6x + 15) = -45 \]
First, divide both sides by -5 to simplify: \[ 6x + 15 = \frac{-45}{-5} \] This simplifies to: \[ 6x + 15 = 9 \]
Next, subtract 15 from both sides: \[ 6x = 9 - 15 \] Which gives: \[ 6x = -6 \]
Now, divide both sides by 6: \[ x = \frac{-6}{6} = -1 \]
Thus, the solution is: \[ \boxed{-1} \]
Therefore, the correct answer is B. \( x = -1 \).