Option E is correct. I "will" make an appointment with the dentist soon is the correct answer.

This option uses the present participle form of the verb "make" (making). However, in this sentence, we need the base form of the verb because it follows the auxiliary verb "will" (Option E). So, "making" is not the correct choice in this context.

This option combines the past tense of the auxiliary verb "have" (had) with the base form of the verb "take." However, this combination does not fit well in the sentence structure. Since the sentence is in the present tense ("I make"), using "had take" would create a mismatch in verb tenses. Therefore, Option B is not the correct choice.

This option uses the base form of the verb "make," which is the correct choice in this context. The sentence is in the present tense, and "make" agrees with the subject pronoun "I." So, "make" is a suitable choice for this sentence.

This option uses the past tense of the verb "make" (made). However, since the sentence is in the present tense, using the past tense would create a tense inconsistency. Therefore, Option D is not the correct choice.

This option uses the auxiliary verb "will," which indicates future tense. Since the sentence expresses a future intention ("I will make"), using "will" is appropriate in this context. It signifies that you have a plan or intention to make an appointment with the dentist soon.