Answer:
El nino no quiero correr. Le duelen las piernas.
Explanation:
We say "correr" because in the next sentence it is saying that "his legs hurt" so running would be the cause of his legs hurting.
The complete sentence is El niño no quiere correr mucho. Le duelen las piernas. (Correct choice: correr)
In this question we must fill the blank of a sentence in Spanish, in which the auxiliar verb "querer" is used and whose grammatical construction is presented below:
Subject + auxiliar verb "querer" + verb in infinitive form + complement.
The correct choice depends on the context behind the sentence:
El niño no quiere correr mucho. Le duelen las piernas.
To learn more on sentences in Spanish, we kindly invite to check this verified question: https://brainly.com/question/16232523