​$$\sqrt{8 - 2\sqrt{15}}$$​ is equal to:

Correct option is B

Given:

​$$\sqrt{8 - 2\sqrt{15}}$$​​

Formula Used: 

​$$(a - b)^2 = a^2 - 2ab + b^2$$ 

Solution:

​$$\sqrt{8 - 2\sqrt{15}}\\ =\sqrt{(5+3-2\times\sqrt5 \times \sqrt3)}\\= \sqrt{(\sqrt{5} - \sqrt{3})^2}\\ = \sqrt{5} - \sqrt{3}$$​​