AMC 12 2015b Problem 17

An unfair coin lands on heads with a probability of $\tfrac{1}{4}$. When tossed $n$ times, the probability of exactly two heads is the same as the probability of exactly three heads. What is the value of $n$ ?

\textbf{(A)} 5 \textbf{(B)} 8 \textbf{(C)} 10 \textbf{(D)} 11 \textbf{(E)} 13