Final answer:
The yoga pose that does not stretch the psoas muscle is the Forward Fold. This pose focuses on the muscles of the back of the legs and spine rather than the hip flexors.
Step-by-step explanation:
The yoga pose that does not stretch and lengthen the psoas muscle is d. Forward Fold (Uttanasana). The psoas muscle is primarily involved in flexing the hip and spinal column. When performing a Forward Fold, the action is more about elongating the muscles along the back of the legs and the spine rather than targeting the hip flexors. In contrast, poses like Camel (Ustrasana), Pigeon (Eka Pada Rajakapotasana), and Upward Facing Dog (Urdhva Mukha Svanasana) involve extension of the hip or spine and therefore can stretch and lengthen the psoas muscle.