式子a² ab3ab5 化简正确的是（   ）

A：a ${}^{\frac{11}{4}}$ b ${}^{\frac{11}{4}}$

B：a ${}^{\frac{11}{4}}$ b ${}^{\frac{11}{2}}$

C：a ${}^{\frac{11}{4}}$

D：b ${}^{\frac{11}{4}}$