Which additional word or words in the sentence should be capitalized?

Is your parents' anniversary on jan. 15 or feb. 15?

Choose all answers that are correct.

a. Feb.

b. Anniversary

c. Parents'

d. Jan.

a d

The words that should be capitalized in the sentence are: Jan. and Feb.

The reasoning for capitalizing those two words are because they are abbreviations of the months January and February. They are capitalized because months are considered proper nouns.