Betsie tried to solve an equation step by step. \qquad\begin{aligned} 3(a+7)& =-33 \\ a+7& =-11& \green{\text{step } 1} \\ a& =-4& \blue{\text{step } 2} \end{aligned} 3(a+7) a+7 a =−33 =−11 =−4 step 1 step 2 find betsie's mistake. choose 1 choose 1 (choice a) a \green{\text{step }1}step 1start color #28ae7b, start text, s, t, e, p, space, end text, 1, end color #28ae7b (choice b) b \blue{\text{step }2}step 2start color #6495ed, start text, s, t, e, p, space, end text, 2, end color #6495ed (choice c) c betsie did not make a mistake.