The property of inequality that justifies the steps shown in the solution process is the Multiplication Property of Inequality.
In the given steps, the original inequality \( \frac{4}{3}d \geq -20 \) is multiplied by \( \frac{3}{4} \) to isolate \( d \). Since \( \frac{3}{4} \) is positive, the direction of the inequality remains the same.
So the correct response is: Multiplication Property of Inequality.