Concept: Use inverse trigonometric identities to rewrite each term and simplify the expression.Explanation:Let A=cos−1(−31) and B=sin−1(31).We know cos−1(−x)=π−cos−1(x).So, A=π−cos−1(31).Also, sin−1(x)=2π−cos−1(x).Thus, B=2π−cos−1(31).Subtract B from A:A−B=[π−cos−1(31)]−[2π−cos−1(31)]=2π.Therefore,sin(cos−1(−31)−sin−1(31))=sin(2π)=1.Answer:1 (Option A)