The steps shown in the solution process involve multiplying both sides of the inequality by the fraction \( \frac{3}{4} \). The relevant property that justifies this step is the Multiplication Property of Inequality.
In this case, multiplying both sides of the inequality by a positive number (which \( \frac{3}{4} \) is) preserves the direction of the inequality. Therefore, the correct response is:
Multiplication Property of Inequality.