Answer:
B. 121
Step-by-step explanation:
Complete the square.
Take half of the middle term, 22, and square it.
So 11^2 = 121.
Factor the equation so...
(r^2-pr) and (p^2q-pqr)
Factor out (r^2-pr) = r(r-p)
Factor out (p^2q-pqr) = pq(p-r)
Add a negative to r(r-p) to make it -r(p-r)
(pq-r)(p-r) is the answer... I'm sorry I can't explain things well, but I tried.