Answer please? Solve math

Answer:
(a)
Step-by-step explanation:
To rationalise the fraction multiply the numerator/denominator by the conjugate of the denominator.
The conjugate of [tex]\sqrt{3}[/tex] + [tex]\sqrt{x}[/tex] is [tex]\sqrt{3}[/tex] - [tex]\sqrt{x}[/tex]
Hence
[tex]\frac{\sqrt{9}(\sqrt{3}-\sqrt{x} ) }{(\sqrt{3}+\sqrt{x} )(\sqrt{3}-\sqrt{x} ) }[/tex]
= [tex]\frac{3(\sqrt{3}-\sqrt{x} }{3-x}[/tex]
= [tex]\frac{3\sqrt{3}-3\sqrt{x} }{3-x}[/tex] → (a)