How is the underlined pronoun in the sentence used?

(Them is underlined)

Sandy showed them her coin collection.

A.

object of a preposition

B.

indirect object

C.

subject

D.

direct object

The word "them" in the sentence is used as the indirect object. The correct answer would be option B. It is used as the indirect object because it is being affected by the verb used in the sentence. The subject or the doer of the action is "sandy", the verb is "showed" and the direct object is "her coin collection" making "them" as the indirect object.