Final answer:
Alexander gained favor with the Persians after taking over the empire by following their customs himself.
Step-by-step explanation:
Alexander gained favor with the Persians after taking over the empire by following their customs himself (option D). Instead of devastating the empire, Alexander aimed to become the next "Great King" and to win over the Persians by treating them with respect and honor. He maintained the Persian bureaucracy and enlisted Persian soldiers, making a show of sympathy for the Persian subjects rather than trying to intimidate them.