Final answer:
The statement is False; the back foot must remain firmly planted on the mat during the Warrior II pose to maintain the correct posture and stability.
Step-by-step explanation:
The statement is False. In the Warrior II (Virabhadrasana II) pose, the back foot should remain planted firmly on the mat. When performing Warrior II, one should position the front foot pointing straight ahead and align the front heel with the arch of the back foot. The back foot should be perpendicular to the front foot or turned in slightly, with the outer edge of the foot pressing into the mat to help maintain balance. The legs are active and strong, with your front knee bent and your back leg straight. Lifting the back foot off the mat in this pose would alter the foundation and could potentially lead to imbalance or injury.