The correct answer is: A. will have
The sentence is in the future tense, so the correct verb form should also be in the future tense. The verb “to get” can be used in the future tense in a number of ways, but in this case the most likely meaning is “to prepare” or “to make ready.” In this context, the only option that makes sense is “will have,” which indicates that the action of getting ready will take place before the event of visiting the house.
The other options are not as likely in this context. “Shall have” is a formal way of saying “will have,” but it is not commonly used in everyday speech. “Are” is the present tense form of the verb “to be,” and it does not make sense to say that someone “is” getting ready for something that will happen in the future. “Were” is the past tense form of the verb “to be,” and it does not make sense to say that someone “were” getting ready for something that has not yet happened.
In conclusion, the correct answer is “will have.” This is because the sentence is in the future tense, and the verb “to get” can be used in the future tense to mean “to prepare” or “to make ready.” The other options are not as likely in this context.