Review the Slides on definite and indefinite articles as needed as you do this.
Definite articles mean the: el, la, los, las.
Indefinite articles mean a, an, some: un, una, unos, unas.
Pay attention to the endings of the words to make sure they match in gender and number.
You can keep trying on this in the time allowed to try for a perfect score before you submit this on Classroom.