Concept:Inverse variation means product is constant. Direct variation means ratio is constant.
Explanation:1. x and y vary inversely: xy = constant → matches C.
2. Inverse variation of p and q: p ∝ 1/q → matches D.
3. Direct variation of m and n: m ∝ n → matches G.
4. Given (x=5, y=2.5) and (y=5, x=10): x/y = 5/2.5 = 2 and 10/5 = 2, constant ratio → direct proportion → matches A.
5. Given (x=10, y=5) and (x=20, y=2.5): xy = 50 and 50, constant product → inverse variation → matches H.
6. x and y vary directly: they are directly proportional → matches F.
7. Inverse variation: decreasing x increases y → matches B.
8. Direct variation: decreasing x decreases y → matches E.
Answer:Option A: 1-C, 2-D, 3-G, 4-A, 5-H, 6-F, 7-B, 8-E.