Answer:
B
Step-by-step explanation:
Using the rule of exponents
[tex]a^{\frac{m}{n} }[/tex] ⇔ [tex]\sqrt[n]{a^{m} }[/tex]
Given
f(x) = [tex]16^{x}[/tex], then when x = [tex]\frac{1}{2}[/tex]
f([tex]\frac{1}{2}[/tex] ) = [tex]16^{\frac{1}{2} }[/tex] = [tex]\sqrt[2]{16}[/tex] = 4
