What is the definition of e-commerce?

The definition of e-commerce refers specifically to the buying and selling of goods and services over the internet. This encompasses a broad range of activities that occur online, including transactions, product listings, online marketing, and customer service related to the purchase experience. E-commerce represents the whole marketplace that operates in the digital realm, involving not just the transaction itself but also browsing, selection, and delivery processes in the virtual space.

The other options describe related but distinct concepts. The development of electronic payment systems is a crucial aspect of e-commerce, enabling online transactions; however, it does not encompass the entirety of what e-commerce represents. Market analysis for online businesses is an important strategic activity to understand consumer behavior and market trends, but it is more about research rather than the transaction processes that define e-commerce. Finally, the physical retailing of products through electronic means does not accurately reflect e-commerce, as it suggests a blending of in-person retail with digital platforms rather than purely online transactions. Thus, option A captures the full scope of e-commerce succinctly and accurately.