Answer:
Through is a preposition
Step-by-step explanation:
This question can be easily answered by using the process of elimination. It can be inferred that 'Them' is mostly used to objectify something, so it is an objective pronoun. 'That' is most usually an adverb, but can also be an adjective and even conjunction. 'Those' is considered a demonstrative adjective because it is usually used when referring to something in a sentence. This obviously leaves you with 'Through', this can be easily remembered as a preposition because of its prepositional definition; "in and out of".
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