Statement: Highly brilliant and industrious students do not always excel in the written examination.
Assumptions:
1. The written examination is good mainly for mediocre students.
2. The brilliant and industrious students cannot always write good answers in the exam
Answer: B
II explains the fact given in the statement and so is implicit. Nothing about 'mediocre students' is mentioned in or can be deduced from the given statement. So, I is not implicit