The correct answer is: B. a product which is produced simultaneously with other products and is of similar value to at least one of the other products.
A joint product is a product that is produced simultaneously with other products from the same starting material. The products are of similar value, and the costs of production are allocated to them based on their relative sales value.
Option A is incorrect because a product which is later divided into many parts is not necessarily a joint product. For example, a car is not a joint product with its individual parts, such as the engine, the transmission, and the body.
Option C is incorrect because a product which is produced simultaneously with other products but which is of a greater value than any of the other products is not necessarily a joint product. For example, gold is not a joint product with silver, even though gold is more valuable than silver.
Option D is incorrect because a product produced jointly with another organization is not necessarily a joint product. For example, a product that is produced by a joint venture between two companies is not necessarily a joint product.