Match each noun with the correct indefinite article.

un
une
des

casquette, shorts, maillot de bain

une casquette, des shorts, un maillot de bain

To match each noun with the correct indefinite article, we need to consider the gender and number of each noun.

1. "Casquette" is a feminine singular noun, so it takes the indefinite article "une".
2. "Shorts" is a masculine plural noun, so it takes the indefinite article "des".
3. "Maillot de bain" is a masculine singular noun, so it takes the indefinite article "un".

Therefore, the correct matches are:

- Casquette: une
- Shorts: des
- Maillot de bain: un

casquette - une

shorts - des
maillot de bain - un