1. **State the problem:** Find the product of the binomials $$(4x + 3)(4x - 3)$$. 2. **Formula used:** This is a difference of squares pattern, which states: $$ (a + b)(a - b) = a^2 - b^2 $$ 3. **Identify terms:** Here, $a = 4x$ and $b = 3$. 4. **Apply the formula:** $$ (4x + 3)(4x - 3) = (4x)^2 - 3^2 $$ 5. **Calculate squares:** $$ (4x)^2 = 16x^2 $$ $$ 3^2 = 9 $$ 6. **Write the final expression:** $$ 16x^2 - 9 $$ 7. **Conclusion:** The product is $$16x^2 - 9$$. This matches the last answer choice.