Concept:Use laws of exponents to simplify each term and compare powers of equal bases.Explanation:First, simplify (45)12=512/4=53.Next, (2)6=26/2=23.Multiply them: 53×23=(2×5)3=103.The right side is ((2×5)3)x=(103)x=103x.Equate both sides: 103=103x.Since bases are equal, set exponents equal: 3=3x, so x=1.Answer:B. 1