Concept:The Remainder Theorem states that when a polynomial p(x) is divided by (x−a), the remainder is p(a).Explanation:Let p(x)=−2x3+6x2+17x−21.Here, the divisor is (x+1), which can be written as (x−(−1)).So, the remainder is found by evaluating p(−1).Substitute x=−1 into p(x):p(−1)=−2(−1)3+6(−1)2+17(−1)−21p(−1)=−2(−1)+6(1)−17−21p(−1)=2+6−17−21p(−1)=8−38=−30Answer:The remainder is −30.Correct option: C. −30.