Final answer:
The correct form of the verb 'comprar' to fill in the blank in the sentence is 'compra'.
Step-by-step explanation:
The correct form of the verb comprar to fill in the blank in the sentence would be option D. compra. The sentence would then read: Hilda no puede compra una camiseta nueva. The verb form should agree with the subject of the sentence, which is Hilda, a third-person singular noun, necessitating the use of the third-person singular form of the verb.
Learn more about verb forms in Spanish