Which term describes temporary exhibits of vendor's merchandise usually held in convention centers or hotels?

The term that accurately describes temporary exhibits of vendor's merchandise held in convention centers or hotels is a trade show. Trade shows serve as a platform for businesses to showcase their latest products and innovations to potential buyers, industry enthusiasts, and the general public. These events are typically organized around specific industries and provide opportunities for networking, learning, and making business transactions.

During a trade show, vendors can create a visually appealing display of their merchandise, interact directly with attendees, and often secure sales or business leads. This format is particularly effective in industries such as fashion, technology, and consumer goods, where companies aim to reach a concentrated audience interested in their offerings.

The other terms do not relate to the concept of temporary merchandise exhibitions; brand loyalty refers to consumers' commitment to repurchase a preferred product, a niche market signifies a specific, targetable segment of a larger market, and cash flow relates to the inflows and outflows of cash within a business. Thus, the characteristics and purpose of a trade show make it the correct answer in this context.