Final answer:
William altered his strategy during the Battle of Hastings by implementing a feigned retreat, baiting the enemy into a vulnerable position to be counterattacked by his cavalry-dominant forces. The correct option is D.
Step-by-step explanation:
During the Battle of Hastings, William changed his battle strategy by ordering a feigned retreat. This tactic involved having his cavalry advance quickly and easily retreat, which caused confusion and scattered the opponent's defenses, enabling the infantry to then invade.
This strategy was flexible, intimidating, and is reflected in the historical depiction of the cavalry on the Bayeux Tapestry, indicating that the Normans were a cavalry-dominant army.
Feigned retreats were a common tactic in historical battles, as they exploited the enemy's pursuit reflex and could lead to ambushes and counterattacks, and this maneuver proved successful for William at Hastings. The correct option is D.