The university computer lab is having difficulty controlling its costs. Analysis showed that a key issue is the cost of printer supplies (ink, paper, and machine repair). Which strategy is likely to reduce costs the most, if typical student use is 200 copies per month?

A. Plan A: requiring students to pay 12 cents per copy

B. Plan B: charging a fee of $20 for the first 100 copies per month, then 10 cents per copy thereafter C. Plan C: charging a fee of $10 for the first 50 copies per month, then 15 cents per copy thereafter D. Plan D: adding a flat lab fee of $30 per academic term E.