JAMB Use of English 2008 Question 30

Select the option that best explains the information conveyed in the sentence: Ado and Abu are always together these days. They must be up to something.

1. A.They must have reconciled after their quarrel
2. B.They are probably planning something bad
3. C.They are capable of a praiseworthy achievement
4. D.They bear some responsibility for what has happened.