Answer:
The words that would make sense are:
<em><u>¿Cuántas</u></em><em> </em>patas tiene un gato?
Uno, dos, tres y<em> </em><em><u>cuatro.</u></em>
Explanation:
The song means,
<u>"How many legs does the cat have?</u>
<u>One, two three, and four."</u>
