Final answer:
The sentence 'Connor and I met up with them after the show.' uses the correct form of the pronoun.
Step-by-step explanation:
The correct sentence that uses the appropriate form of the pronoun is: Connor and I met up with them after the show.
In this sentence, 'Connor and I' is the subject of the sentence, and 'them' is the correct objective pronoun to use when referring to the people I met up with after the show.
The other options contain errors in pronoun usage. In the first sentence, 'he and Lindsey' should be 'him and Lindsey' as 'him' is the objective pronoun. In the second sentence, 'him' should be 'he' as 'he' is the subjective pronoun. In the fourth sentence, 'them' should be 'they' as 'they' is the subjective pronoun.
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