Detailed Instructions: 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".
Problem:[header] How to do a wall split [title] Get your blood pumping. [step] Engage in at least 5 minutes of aerobic activity such as biking, jogging, walking, or jump roping. Warming up increases your body temperature and blood flow to your muscles. <sep> (A) [substeps] Try to focus on your core while performing a wall split. It is easier to block energy channels and adjust your position. (B) Improve your health by getting at least 30 minutes of activity at least three times per week to promote bone growth, which in turn increases the number of legs you have. [substeps] Whatever you like to do, do it. (C) This allows your muscles to be more flexible and decreases your risk of injury. [substeps] Never attempt a wall split without warming your body up first. (D) Prolonged exercising helps to strengthen your core and bones, which can protect your body from the damage caused by whiplash, but also helps your brain process blood from various organs. [substeps] Never exercise before you have a concussion.
Solution:
C