Answer:
The correct answer is D. (Mejore)
Step-by-step explanation:
In Spanish, the 3rd person (singular and plural) of the present subjunctive is used to form the formal mandates.
In the informal mandates, the 3rd person of the singular of the present indicative is used to form the affirmative mandates and the 2nd person (you) of the present of the subjunctive to form the negative mandates.
In the example of the formal mandate:
AFFIRMATIVE: ¡Hable!
NEGATIVE: ¡No hable!
In the example of the informal mandate:
AFFIRMATIVE: ¡Habla!
NEGATIVE: ¡No hables!