Concept:Use the laws of exponents to combine powers with the same base.Explanation:First, apply the multiplication rule: am×an=am+n.So, 57×5−4=57+(−4)=53.Now the expression becomes 5353.Apply the division rule: anam=am−n.Thus, 5353=53−3=50.Any non-zero number raised to the power zero equals 1, so 50=1.Therefore, the simplified value is 1.Answer:B. 1