Final answer:
The best example of a good managed through B2C transactions among the options provided is an iTunes song. Non-excludable goods or services like police protection, roads, and primary education are publicly accessible and provided without charge at the point of use.
Step-by-step explanation:
Among the options provided, an example of a good managed through B2C (Business-to-Consumer) transactions would be b. iTunes song. This is because iTunes songs are digital goods sold directly to the consumer via the Internet, which is typical of B2C sales. The other options, such as office furniture, virus protection software, and fishing license application and fee, can also be B2C transactions but are not as clear-cut examples as a digital music purchase which is inherently designed for direct consumer consumption online.
Regarding the question about non-excludable goods or services, which means those that cannot be withheld from people and must be provided without direct payment (such as public goods), the non-excludable items are a. police protection, c. roads, and d. primary education. These are typically provided by the government and accessible to all individuals without direct charges at the point of use.