The correct answer is B. For.
People work for a variety of reasons, including to earn money, to feel a sense of accomplishment, to socialize, and to learn new skills. However, the most common reason people work is to earn money. Money is necessary to purchase goods and services, to pay for housing and food, and to save for the future.
The other options are not as relevant to the question. Option A, “In,” could be interpreted to mean that people work in a specific location, such as an office or factory. However, this is not always the case. Many people now work from home or remotely. Option C, “Around,” could be interpreted to mean that people work in a specific industry or field. However, this is also not always the case. People can work in a variety of industries and fields, and they may not always have a choice in which industry or field they work in. Option D, “Why,” could be interpreted to mean that people work for a specific reason. However, as mentioned above, people work for a variety of reasons.
In conclusion, the correct answer to the question “For whom do the people work and earn?” is B. For. People work for a variety of reasons, but the most common reason is to earn money.