Given: A function-

Required: To determine the domain of the function.
Step-by-step explanation: The domain of a function is the set of all the input values or x-values at which the function f(x) exists.
The square root of a negative number does not give any real value. Hence, the function will exist for-

Hence, the domain is-
![Domain:\text{ \lparen-}\infty,-4]\cup[4,\infty)](https://img.qammunity.org/2023/formulas/mathematics/college/s7ne9yx9wgg78hz8gpbf54474vf1duka4y.png)
Final Answer: Option D is correct.