2021 ZeMC10 Problems/Problem 2

Problem

Given that Luke's teachers assign homework at the same constant rate, if $3$ teachers can assign $120$ homework assignments to Luke in $1$ hour, how many homework assignments can $1$ teacher assign to Luke in $15$ minutes?

$\textbf{(A) } 10 \qquad \textbf{(B) } 12 \qquad\textbf{(C) } 15 \qquad\textbf{(D) } 120  \qquad\textbf{(E) } 600$