The problem asks for $f(5)$ where the function is defined as $f(x) = 8x - 3$.

To solve:

1. Substitute $x = 5$ into the function: $f(5) = 8(5) - 3$
2. Simplify: $f(5) = 40 - 3 = 37$

Thus, the correct answer is D. 37.

Would you like more details or explanations? Here are 5 related questions to expand on this:

1. What is the general form of a linear function and its components?
2. How do you interpret $f(x)$ in terms of input and output?
3. What other values of $f(x)$ can you calculate, such as $f(10)$?
4. How does changing the coefficient (like $8$) or the constant (like $-3$) affect the function?
5. Can you plot $f(x) = 8x - 3$ to visualize it?

Tip: Always check your substitution and arithmetic to avoid small errors!