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 work out at the beach [title] Walk barefoot in the sand. [step] There's nothing better than going for a nice long walk on the beach. Even a leisurely walk can offer a great workout when you're not wearing any shoes. <sep> (A) You can even go for a jog or paddle to get some fresh air into your lungs. [substeps] Beach workouts that start with jogging or rowing are great for people with mobility difficulties. (B) [substeps] Walking is one the of the oldest forms of exercise. It's a low-impact and low-intensity exercise that many people can perform regardless of their fitness level. (C) It can also help get you moving along the beach, whether you prefer walking or jogging. [substeps] Sunbathing on the beach is a great way to burn calories while exercising, as the sun is drying out your body. (D) It's not hard to cut out some of the pollution from the surrounding ocean by walking barefoot in the sand. [title] Grab some sunscreen at the beach.
B