What happens next in this paragraph?

How to understand pay as you go cell phone plans 
Understand that there is a thin line between pay as you go and prepaid plans. 
Pay as you go minutes or daily rates can last for 30 days or up to a year, depending upon the brand. Prepaid cell plans are usually monthly rates without a contract.
Available choices: (A). Prepaid plans work, provided you follow up with customers and do not give out a card for payment; however, prepaid plans allow you to manage your plan and earn a monthly premium each month. This is because pay as you go is also earned.; (B). Prepaid plans have variable budgeting, with a flat monthly charge. Think about how you are going to pay yourself.; (C). However, sometimes these terms are used interchangeably, since you also " pre-pay " for minutes plans. Use a pay as you go plan if you have unlocked cell phones at your disposal.; (D). Usually, in most plans, you will have an option of doing this in advance of making your plan. The main advantage to having a careful budget and paying what you can in advance of the money you will need on the day of the plan is that will help your plan mix up normally.;
(C).