Final answer:
The correct form of the verb tocar to complete the sentence 'Anoche yo la guitarra' is toqué.
Step-by-step explanation:
The correct form of the verb tocar to complete the sentence 'Anoche yo la guitarra' is A. toqué.
In Spanish, verb conjugation depends on the subject pronoun and the tense of the sentence. Since the subject of the sentence is 'yo' (I) and the sentence is in the past tense, the correct conjugation for the verb 'tocar' is 'toqué'.
For example: Anoche yo toqué la guitarra. (Last night I played the guitar.)
Learn more about Spanish verb conjugation