They can talk about what they like to do
The correct option is B.
Vitamin B12 are a set of water soluble related substances, which are very important for the proper functioning of some body enzymes and they are usually found together in the same food. Foods that are rich in Vitamin B12 include:meat, fish, poultry, egg and dairy. Some people who are vegetarians and who do not eat these kind of food will benefit greatly from taking vitamin B12 supplement.
Most likely, it would be so that they could distribute their finances