Eres alto translates to you're tall and Usted es alto translates to You are tall.
So I'm going to go with D
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You use preterite to describe an action that took place and was fully done, Ex. José entro a la habitación, you can see John went into the room, he completed the action. On the other hand, imperfect tense doesn't specificate if the action was completed, Ex. José entraba a la habitación, it doesn't tell us if José fully entered the room.
Hey!
While both are often used, the most accurate answer is probably answer a:
The "personal a" is necessary.
Why?
Well, when we say: "Quiero a mi esposo Jorge" we are talking specifically about the husband, that is: "lo quiero a él". Therefore, the "a" is usually used on these occasions.