- A
- B
- C
- D
Step-by-Step Solution
Simplify the bracket: 7 − 7 = 0, so the last expression is (−9) ÷ 0 — division by zero, which is undefined. The other three all have values: 0 ÷ (−9) = 0, (−9) ÷ (−9) = 1 and (−9) × 0 = 0. Dividing zero BY a number is perfectly legal; dividing a number by zero is not, and the answer is not 0 either.
Answer: D)