Step 1: Understanding prone line asanas.
Prone line asanas are yoga poses that are performed lying face down on the ground. These asanas target the back and the chest and are performed while facing the floor.
Step 2: Analyzing each asana.
- (A) Bhujang-asana: Bhujang-asana (Cobra pose) is performed in a prone position, where the chest is lifted while the lower body remains on the ground.
- (B) Makar-asana: Makar-asana (Crocodile pose) is a prone position where the body is lying face down with the arms and legs relaxed.
- (C) Supt-vajrasana: Supt-vajrasana (Reclining Thunderbolt pose) is not a prone asana; it is performed sitting on the legs and reclining back.
- (D) Shalabhasana: Shalabhasana (Locust pose) is a prone pose where the body is lifted from the floor with support from the chest and legs.
Step 3: Conclusion.
Therefore, the correct answer is (C) Supt-vajrasana, as it is not a prone line asana.
Final Answer: (C) Supt-vajrasana.