Final answer:
The correct answer to complete the series is 'O el caballo.' Understanding gendered nouns is crucial in Spanish grammar.
Explanation:
The correct option to complete the series of words is 'O el caballo.'
In the given series, each pair consists of a feminine noun and its masculine counterpart. In this case, 'la yegua' (the mare) corresponds to 'el caballo' (the horse) in the masculine form.
Understanding gendered nouns in Spanish is essential for proper grammar and language usage.
Learn more about Spanish nouns and gender
