Correct option is B
The correct substitution is (b)
Everyone was sincerely and positively.
Explanation: “Everyone” is a singular
indefinite pronoun, so it takes a singular verb – "was" not "were."
Correct sentence: Everyone was sincerely and positively ready...
Grammatical Rule Used:
�� Indefinite pronouns like everyone, someone, anyone, nobody are
singular and must take singular verbs.
Example: Everyone wants to succeed. (not want)