Learn Portuguese (Portugal): Temos maçãs. Quais prefere ela? - We have apples. Which ones does she prefer?

Qual translates to "which" or "what" for singular nouns, while quais is the plural form ("which ones"). Because we are asking about maçãs (apples, plural), we must use quais.

Since maçãs is feminine, shouldn't quais be feminine too?

No, because qual and its plural quais are gender-neutral! Unlike question words like quantos and quantas (how many) that change based on gender, quais stays exactly the same whether it refers to feminine nouns like maçãs or masculine nouns.

Why is it prefere ela instead of ela prefere?

In Portuguese, when a question starts with a question word like quais, the subject pronoun (like ela) is usually moved right after the verb or to the end of the sentence. Quais prefere ela? is the most natural word order in European Portuguese.

Why is there no word for "we" before Temos?

In Portuguese, the verb ending usually tells you exactly who is doing the action. Temos is the "we" form of the verb ter (to have). Because it can only mean "we have", adding the word nós (we) is unnecessary and is usually dropped.