Step 1 :The question is asking for the composition of two functions, $f$ and $g$, evaluated at $4b$. The composition of functions is a concept in mathematics where you apply one function to the result of another function. In this case, we are asked to find $(f \circ g)(4b)$, which means we first apply the function $g$ to $4b$, and then apply the function $f$ to the result.
Step 2 :To solve this, we first need to find $g(4b)$, then substitute this result into $f(x)$.
Step 3 :We have calculated the composition of the functions $f$ and $g$ at $4b$. The result is $(4b - 5)^2 - 1$. This is a quadratic expression in terms of $b$.
Step 4 :Now, we need to simplify this expression to match one of the given options.
Step 5 :We have simplified the expression to $16b^2 - 40b + 24$. This matches one of the given options, so this is the final answer.
Step 6 :Final Answer: \(\boxed{16b^2 - 40b + 24}\)