Find the incorrect part of the sentence:
He divided the sweets between his five friends.

Correct option is B

Option (b) contains an error.
Detailed explanation: Use among for more than two persons/things when referring to a general distribution within a group. Here, the sweets are distributed to five friends (a group of more than two), so “among his five friends” is required. “Between” is typically used for two entities or when choices/relationships are considered pairwise.
Grammatical rule used: Between is used for two; among for more than two in general distributions.
Example: She divided the chocolates among her three cousins. / The dispute was between Ram and Shyam.
Information booster / exceptions: Between can be used with more than two when relationships are distinct and individual (e.g., “an agreement between the company, the union, and the government”), but competitive exams prefer the traditional rule for distribution contexts— among for 3+.