Final answer:
The preterite form of the verb aprende is aprendí.
Step-by-step explanation:
The correct answer is D. aprendí.
The preterite form of the verb aprender (to learn) in the first-person singular (yo) is aprendí. In the given sentence, the subject is yo, and the action of learning in the past tense is represented by the preterite form aprendí.
For example: Yo aprendí mucho en la clase de física ayer (I learned a lot in the physics class yesterday).
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