The correct answer is: B. Natural market.
A natural market is a group of people who are already interested in the product or service you are selling. In the case of insurance, members of a caste or community association are likely to be interested in insurance because they are already familiar with the concept and may have already purchased insurance for themselves or their families.
Immediate group is a group of people who are close to you, such as your family, friends, and co-workers. Centers of influence are people who have a lot of influence over others, such as business leaders, community leaders, and celebrities. References and introductions are people who can recommend you to others.
While all of these groups can be potential customers, natural markets are the most likely to be interested in your product or service. This is because they are already familiar with the concept and may have already purchased insurance for themselves or their families. Additionally, they are likely to trust the recommendations of their friends and family, which can make them more likely to purchase insurance from you.
Therefore, if you are selling insurance, it is a good idea to focus your efforts on natural markets. You can do this by attending events and networking with people in your target market, or by advertising in publications that are read by your target market.