Final answer:
The correct word that completes the sentence is pequeñito.
Step-by-step explanation:
The correct word that completes the sentence is C. pequeñito.
When describing age in Spanish, we use the word años (years) and the verb tener (to have). Since the noun hermano (brother) is masculine, we need to use the masculine form of the adjective pequeño (small), which is pequeñito.
For example, if we were referring to a sister, we would use the feminine form pequeñita.
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