Definition: 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".
Input: [header] How to get better sleep during pregnancy [title] Design an exercise regimen that you can do while pregnant. [step] Make sure that it is not too strenuous and that you cut back on repetitions and overactive sessions as your pregnancy progresses. Exercise will help exhaust you so that you can sleep deeper at night. <sep> (A) Additionally, exercise will help reduce the risk of leg cramps that often occur at night when pregnant. Opt for yoga or tai chi as your exercise choice, as they are both meditative and will allow you some time to relax and be calm while pregnant. (B) Make sure that you begin your exercise regimen at least 5 to 10 days before your baby arrives. As of december 1, the earlier you begin exercise, the greater your chances of expelling vaginitis bacteria. (C) Take active mountain biking or track with you to the gym. Or, do a running class in your neighborhood with a friend. (D) [substeps] For example, you could try some form of yoga, an exercise with arms and legs extended, or ankle weights. Exercise boosts your metabolism by slowing your heart rate, reducing your body's spontaneous response response to stress, and also promotes your overall health.
Output:
A