1. **Problem:** Find the value of the polynomial $p(x) = 5x - 4x^2 + 3$ at $x = 0$. 2. **Formula:** To find the value of a polynomial at a given $x$, substitute the value into the polynomial and simplify. 3. **Substitution:** $$p(0) = 5(0) - 4(0)^2 + 3$$ 4. **Simplify:** $$p(0) = 0 - 0 + 3 = 3$$ 5. **Answer:** The value of $p(x)$ at $x=0$ is $3$. Hence, the correct choice is (a) 3.