If a ⊕ b = (a × b) + b, then 5 ⊕ 7 equals to?

Answer: Option C

$$\begin{array}{rl}& a\oplus b=\left(a\times b\right)+b\\ & \Rightarrow 5\oplus 7\\ & =\left(5\times 7\right)+7\\ & =35+7\\ & =42\end{array}$$