Which of the following is not an example of a barter arrangement?

A babysitting cooperative run by neighborhood parents involves an organized arrangement where parents provide babysitting services for one another, typically without the exchange of money. In this context, while parents are exchanging services, the cooperative may not necessarily operate as a barter arrangement in the traditional sense. Bartering typically refers to a direct exchange of services or goods between parties, often on a one-to-one basis with an implicit value assigned to the exchanged items or services.

In contrast, trading services between two businesses is a classic example of a barter arrangement, as it directly involves the exchange of services with the expectation that both parties benefit equally. Similarly, exchanging goods without monetary payment represents a straightforward barter situation, as it clearly shows the idea of swapping items rather than involving any cash transaction. Service exchanges for promotional advertising also fit the definition of bartering since it is an exchange of services that compensates one party with another form of value, here in the form of advertising instead of cash.

Thus, the reason "A" is not considered a traditional barter arrangement is that it functions more as a cooperative service model, where the exchange of services might not be calculated in direct, equivalent terms as typically seen in barter systems.