Answer:
In the sentence, "grandma" would be considered an indirect object.
Step-by-step explanation:
An indirect object refers to the person to or for whom something is done. Verbs such as "buy" and "give" tend to require both a direct and an indirect object. The direct object is the thing being bought or given. The indirect object is the person receiving the thing.
In the sentence we are analyzing here, the direct object is the thing Jason bought - the puzzle. The person who is receiving the puzzle is "grandma". Therefore, we can safely say that "grandma" is the indirect object of the sentence.