This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to stay faithful if your boyfriend is far away from you
Keep in touch.
Have contact with him through his phone, email, skype, etc. Contact him often, and make sure to tell him that you miss him, love him, are giving him good wishes, and so on.

OPT:
[A]. If you are already dating someone, make an effort to keep in touch. When he does see you or texts you, remind him of the good times in your life.;
[B]. If you notice his absence, get back to him. Be sure to call him frequently too so that you can stay in touch.;
[C]. This will remind you how sweet, nice, and/or caring he is. You wouldn't want to cheat on a good person.;
[D]. Your relationship is not over after two or three months. If you call him frequently, be sure to keep in touch.;
The answer is:
[C].