Answer:
b. cantas
Step-by-step explanation:
Tú cantas translates to You sing.
canto would be used if you were saying , "I sing" or "Yo canto"
canta is used if you're saying , "Ella canta" or "She sings"
cantamos is used if you're using it as a group , "Nosotros cantamos" or "We sing."
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