FERMAT 2021 Problem 11

In the sum shown, P, Q and R represent three different single digits. The value of P+Q+R is

\begin{array}{r} P 7 R \\ +\quad 39 R \\ \hline R Q 0 \end{array}

Answer Choices
A. 13
B. 12
C. 14
D. 3
E. 4