Correct option is A
Explanation of the Correct Answer: · "Everyone" is a singular pronoun, so it must take a singular verb.
· "Were trying" is incorrect because "were" is plural and does not match "everyone."
· The correct phrase should be "Everyone was carefully trying to..."
Why Are the Other Options Incorrect? · (b) "Had carefully trying" → Incorrect; "had" needs a past participle ("tried"), not "trying."
· (c) "Everyone were" → Incorrect; "were" is plural but "everyone" is singular.
· (d) "Did carefully tried" → Incorrect; "did" is followed by the base verb ("try"), not "tried."
Thus, the correct answer is (a) Everyone was carefully trying to.