Fill in the blanks with the most appropriate option:-

I _________ an iPhone.

don’t have

The most appropriate option to fill in the blanks is don't have.

The sentence "I don't have an iPhone" is in the present tense, and it is negating the possession of an iPhone. The other options are not as appropriate.

• Doesn’t have is the third person singular present tense of the verb "to have". This does not make sense in the context of the sentence, as the speaker is talking about themselves, not someone else.
• Don't has is not a grammatically correct sentence.
• Have not is the negative form of the present perfect tense of the verb "to have". This does not make sense in the context of the sentence, as the speaker is not talking about an action that has not happened in the past, but the current state of not having an iPhone.