Task: Reasoning / MCQA
User instruction:
Budget ≤ 5,000 USD

Within one month after “Eco-friendly Day,” we must actually reduce at least 1,200 single-use cups.
For each option, “actual reduction” is calculated by multiplying the potential reduction by the expected participation rate.

Option        Activity        Cost        Potential Reduction (cups)        Expected Participation
A        Plastic documentary screening & discussion        6,800 USD        1,000        60 %
B        Distribution of 200 stainless tumblers        4,000 USD        2,400        70 %
C        Recycling quiz contest + 50 tumblers for the winning team        1,000 USD        2,000        40 %
D        Automatic washer for reusable cups in the cafeteria        4,800 USD        1,500        75 %
Question: Which is the only option that simultaneously meets both the target (≥ 1,200 cups) and the budget (≤ 5,000 USD)?

Evaluation criteria:
The correct answer is B.
Apart from distributing 200 stainless tumblers, the other three options are all incorrect.
The plastic documentary screening and discussion (Option A) costs 6,800 USD, exceeding the budget.