The hotel was not too expensive

The correct answer is option A.

Question tag -It is used when one wants to reconfirm ones statement.It is a statement followed by a question.

If the statement is positive, question tag will be negative and vice versa.

For ex- Shyam is working in a bank, isn't he?

Question tags are formed with the auxiliary or modal verb from the statement and the appropriate subject.

A subject pronoun comes after an auxiliary or after `to be' form of the verb & is used to replace the noun.

Here in the given question-

Hotel was not too expensive, wasn't it?

Since the statement /main part of the sentence is in positive form, question tag will be negative.

Here `was' is used in main part of the sentence,so in question tag we use `wasn't'.

(Same verb/(auxiliary,modal,main)as that of the sentence)

To indicate `Hotel',here we used pronoun`it'.

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