ANSWER
B.
[tex]{f}^{ - 1} (x) = {x}^{2} - 3[/tex]
EXPLANATION
Given
[tex]f(x) = \sqrt{x + 3} [/tex]
Let
[tex]y= \sqrt{x + 3} [/tex]
Interchange x and y.
[tex]x= \sqrt{y + 3} [/tex]
Square both sides
[tex] {x}^{2} = y + 3[/tex]
Solve for y
[tex]y = {x}^{2} - 3[/tex]
Therefore the inverse of f(x) is
[tex] {f}^{ - 1} (x) = {x}^{2} - 3[/tex]
