# If $p$ and $q$ are +ve real numbers such that $p^2+q^2=1$ then the maximum value of $(p+q)$ is

$(a)\;2\qquad(b)\;\large\frac{1}{2}\qquad$$(c)\;\large\frac{1}{\sqrt 2}\qquad$$(d)\;\sqrt 2$

Using AM $\geq$ GM