Question

Quein lava la ropa?

Answer 1

This is asking - Who washes the clothes?
Now, let me ask you WHO does wash the clothes?

Yo lavo la ropa. - I wash the clothes.
Tu lavas la ropa. - You (informal*) wash the clothes.
Usted lava la ropa. - You (formal**) wash the clothes
Él lava la ropa. - He washes the clothes.
Ella lava la ropa. - She washes the clothes.
Nosotros lavamos la ropa. - We (masculine and mixed***) wash the clothes.
Nosotras lavamos la ropa. - We (feminine) wash the clothes.
Ellos lavan la ropa. - Those men/boys wash the clothes./That pair/group of men/boys wash the clothes.
Ellas lavan la ropa. - Those women/girls wash the clothes./That pair/group of women/girls wash the clothes.
Ustedes lavan la ropa. - You guys wash the clothes.

*You (informal): This is when you are speaking to someone like a friend or someone under 18.
**You (formal): This is when you are speaking to someone you respect or someone over 28 such as a teacher or a parent.
***When I say nosotros is masculine and mixed, I am that nosotros means that "we" is a group of boys or "we" is a group of boys and girls.

Answer 2

Remember "tú" has an accent over the "u".