Use Vieta's formula for x² + px + q = 0. For this form, the sum of the roots is -p and the product of the roots is q. The given roots are 1 and -4, so their sum is 1 + -4 = -3. Since sum = -p, we have -p = -3, which gives p = 3. The product 1×-4 = -4 also matches the constant term, so the roots are consistent. Therefore the correct answer is 3.