GMAT Critical Reasoning (CR) | Re: In order to increase revenues, a cell-phone company has

Assumptions: Usage will not change
Market situation will not change (competitors etc.)
No other event affecting costs will happen

A) A rival-company , which charges no start-up fee , offers an unlimited calling plan for $40 per month.It seems out of topic, since the argument is about the company and its own budgeting structure. Still keep it.
B) Two-thirds of the company's customers use less than 500 minutes per month.strengthen, if we assume that usage data will not change
C) Studies have