The correct answer is A. To give an example of how recycling programs exist in countries around the world.
Step-by-step explanation
The text is about the importance of recycling and how it helps to reuse some materials such as plastic, metal, and paper. It also reduces air and water pollution and prevents potentially recyclable materials from being wasted. In one of his paragraphs the autor refers to how recycling has been implemented worldwide by saying "Recycling programs exist in many countries around the world" and later he gives an example of this by saying "For instance, in Germany, containers are placed in railway stations to collect items for recycling ...". According to the above, it can be interpreted that the use of this example is to reference the implementation of recycling worldwide. So the correct answer is A. To give an example of how recycling programs exist in countries around the world.