Answer:
Correct
Step-by-step explanation:
If you have a sentence and think the reader or listener know which particular thing or person you are talking about, then you must use the definite article. In Spanish, there are four definite articles and they are the following:
El - Masculine Singular Form
La - Feminine Singular Form
Los - Masculine Plural Form
Las - Feminine Plural Form
Those definite articles translate into the in English and must agree with the noun it modifies. In this case, the noun is calendario, which is masculine and singular, then the correct matching definite article is el.
So the answer is correct.