Elle mange _ pomme chaque matin.

The sentence Elle mange ___ pomme chaque matin means "She eats ___ apple every morning." The blank requires a determiner before pomme, which is a feminine singular noun.

The correct answer is une (a/one), the feminine singular indefinite article. The sentence describes a habitual action: she eats one apple each morning. Une matches the gender (feminine) and number (singular) of pomme.

The other options are incorrect:

• la (the) is the feminine singular definite article. While la pomme is grammatically valid, Elle mange la pomme chaque matin would mean she eats a specific, identified apple every morning, which is semantically odd for a daily habit
• du is the masculine singular partitive article (used with uncountable nouns like du pain). Pomme is feminine and countable, so du does not agree
• des is the plural indefinite article. Pomme is singular here (no -s), so des does not agree in number

The complete sentence is: Elle mange une pomme chaque matin - She eats an apple every morning.