Final answer:
The correct form of the verb tener to fill in the blank in the sentence is tenga.
Step-by-step explanation:
The correct form of the verb tener to fill in the blank in the sentence 'Quiero una casa que _______ piscina' is option OC. tenga. This is because the sentence is in the subjunctive mood and requires the use of a verb form that expresses doubt or uncertainty. In this case, the verb tener needs to be conjugated to its third person singular form in the present subjunctive, which is tenga.
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