Definition: In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".
Input: [header] How to install a modem [title] Make sure that your modem will work with your internet subscription. [step] While rare, some modems encounter issues when paired with a specific internet company (e.g., comcast). Double-check your modem's compatibility with your current internet subscription before buying (if possible). <sep> (A) [substeps] Generally, you'll have the option of installing a modem while internet subscription is enabled. This is a good option if your internet subscription doesn't normally infuse with internet connection configuration. (B) [substeps] If you find that your modem won't work with your current subscription, try to exchange the modem for a different one that will work, or switch your internet subscription. [title] Find your room's cable output. (C) [substeps] You can buy both individually and separately, if you choose. They may also be possible if your internet subscription has a separate option that allows you to install software for your way-of internet subscription. (D) [substeps] Some modems have difficulty with errors during setup; such errors can result from multiple connectors that run on one particular internet service, which can result in a defective modem. Check your modem's service profile to see if there are any problems with it.
Output:
B