Final answer:
The correct past tense form of the verb llamar in this sentence is llamó.
Step-by-step explanation:
The correct past tense form of the verb llamar in this sentence is llamó. The verb llamar means 'to call' in English. In this sentence, it is conjugated to agree with the subject 'mi mamá' (my mom) in the yo form. So, the correct form is llamó.
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