The correct answer is D. I have worked as a babysitter for my neighbor on the weekends.
Step-by-step explanation:
The perfect tense differs from other tenses because this uses "have" in the present tense as an auxiliary, and this auxiliary is followed by the main verb, which should be in past participle form. Moreover, this tense is used in actions that began in the past and had an effect on the present.
This grammatical structure is used in the sentence "I have worked as a babysitter for my neighbor on the weekends" because this is the only that includes "have" as an auxiliary verb, followed by a past participle verb, which is "worked". Also, this sentence belongs to this tense because the action "I have worked" began in the past and continues in the present.