Concept:Use substitution from one equation into the other to solve for p and q.Explanation:Given: 3p=4q and 9p=8q−12.From 3p=4q, express q in terms of p: q=43p.Substitute q=43p into 9p=8q−12.9p=8(43p)−129p=6p−12Subtract 6p from both sides: 3p=−12Divide by 3: p=−4.Now substitute p=−4 into q=43p.q=43(−4)=−3.Therefore, pq=(−4)(−3)=12.Answer:pq=12, so the correct option is A.