question_answer

If p and q are positive real numbers such that \[{{p}^{2}}+{{q}^{2}}=1,\] then the maximum value of (p + q) is

A)  \[2\]                            

B)  \[\frac{1}{2}\]

C)  \[\frac{1}{\sqrt{2}}\]                            

D)  \[\sqrt{2}\]

E)  None of these