Given the task definition and input, reply with output. In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

[header] How to perform hip flexor stretches [title] Do a yoga camel pose. [step] In addition to stretching the hip flexors, the camel pose will open up the chest and increase the flexibility of the spine. The exercise tightens the waist and strengthens the arms and shoulders as well. <sep> (A) Yogis believe that this posture opens up your respiratory system so that you can take in more oxygen with each breath. They also believe that the exercise helps to open the heart chakra to allow you to feel more connected to the world and to bestow forgiveness where needed in your life. (B) Give yourself a break from the chair and let your head and neck rest against the top of your bar. [substeps] If you're feeling a little fatigued or fatigued, wait a few minutes to give your body time to rest. (C) To do a camel pose, lie down on the floor with your back straight and your feet placed on a park bench. Grip the bars with the weights in your hands. (D) Before attempting these poses, they should be done at home : [substeps] Kneel with your knees bent at a 90 degree angle. Put both of your feet together with your toes pointed in towards each other.
A