Fill in the following sentence: Los hermanos del padre es
1. el tio
2. el primo
3. los tios
4. los primos

It translates to:
The brothers of the father are ___

1. El tío - The uncle
2. El primo - The cousin
3. Los tíos - The uncles
4. Los primos - The cousins

We know that the brothers of our fathers are our uncles so 2 and 4 can be marked out.

The sentence is plural so you would choose the plural word.

3. Los tíos

Also.
The sentence in Spanish should be:
Los hermanos del padre son los tíos.

Not sure why “es” is there instead of “son.”