Answer:
The verb is conjugated correctly.
Explanation:
The sentence is "Ud. abre la puerta cada mañana". "Ud." us a common abbreviation for "usted", the formal second person in Spanish, used when speaking in formal settings or to show respect to the listener. Unlike with "tu", the conjugation is different. For the verb "abrir" (to open), the proper simple present conjugation is "abre" which is why the verb is conjugated correctly.
