Choice A is the correct answer. This real-world constraint problem models resource allocation with inequalities.

1. Total usage: $8.5 + d$ must not exceed 15 GB
2. Set up: $8.5 + d \leq 15$
3. Solve: Subtract 8.5: $d \leq 15 - 8.5$
4. Calculate: $d \leq 6.5$ GB

?�� Strategic Tip: Maximum capacity problems use $\leq$ to ensure totals don't exceed limits.

Choice B is incorrect because$\geq 6.5$ would mean using at least 6.5 GB more, which could exceed the 15 GB limit. Choice C is incorrect because it adds 8.5 and 15 instead of subtracting, misunderstanding the constraint. Choice D is incorrect because while structurally close, using $\geq$ reverses the constraint logic.