question_answer

If \[P=\sqrt[16]{7}+\sqrt[16]{5}\], \[q=\sqrt{7}+\sqrt{5}\], \[r=\sqrt[8]{7}+\sqrt[8]{5}\],\[s=\sqrt[16]{7}-\sqrt[16]{5}\] and \[t=\sqrt[4]{7}+\sqrt[4]{5}\] then which one of the following is a rational number?

A)  pqrt                             

B)  pqrst

C)  prt                              

D)  qrt

E)  None of these