Correct option is B
The correct substitution is
"friendliest" because it is the superlative form of
"friendly." Since the sentence is comparing one person against an entire group, the superlative form is required.
Grammatical Rule Used:
· When comparing more than two entities, the superlative degree (
friendliest) is used.
· The
comparative degree (friendlier/more friendly) is used when comparing two people.
Example:
·
John is the friendliest person in the office.
·
Between John and Steve, John is friendlier.
Other options and why they are incorrect:
·
Most friendly – Though sometimes used, "friendliest" is the more natural and grammatically correct choice.
·
Friendlier – Comparative degree (used for two people, not a group).
·
More friendly – Less common and less idiomatic than "friendlier."