The square root of $$\left( {7 + 3\sqrt 5 } \right)$$  $$\left( {7 - 3\sqrt 5 } \right)$$   is

A. $$\sqrt 5 $$

B. 2

C. 4

D. $$3\sqrt 5 $$

Answer: Option B

Solution(By Examveda Team)

$$\eqalign{ & \sqrt {\left( {7 + 3\sqrt 5 } \right)\left( {7 - 3\sqrt 5 } \right)} \cr & = \sqrt {{{\left( 7 \right)}^2} - {{\left( {3\sqrt 5 } \right)}^2}} \cr & = \sqrt {49 - 45} \cr & = \sqrt 4 \cr & = 2 \cr} $$