Which is an example of external staff training?

Providing product knowledge by a vendor is indeed an example of external staff training, as it involves instruction or guidance coming from an outside source rather than from internal employees. When vendors offer training, they bring their expertise and a distinct perspective related to their products, which is valuable for staff to understand the selling points, features, and uses of the products they will be dealing with. This type of training enhances product knowledge, improves customer service, and can lead to increased sales effectiveness.

In contrast, reading trade publications, role-playing scenarios, and cross-training with other departments all rely on internal methodologies or resources. While these methods are beneficial for staff development, they do not involve an external entity providing specialized training or knowledge. Thus, the focus on external expertise in the correct answer highlights the significance of leveraging outside resources to enhance employee skills and knowledge.