Concept:Laws of exponents: When multiplying powers with the same base, add the exponents.Explanation:Verify each option using an example. Let x=2, a=1, b=2.Option A: xa×xb=xab? 21×22=21×2=22=4, but actual product is 2×4=8. False.Option B: xa×xb=xa+b? 21×22=21+2=23=8. Matches. True.Option C: xa×yb=(xy)ab? Bases differ, rule does not apply. Example: 21×32=2×9=18, while (6)1×2=62=36. False.Option D: xa÷xb=xa/b? 21÷22=2÷4=0.5, but 21/2≈1.414. False.Hence only option B is correct.Answer:Option B: xa×xb=xa+b