“M-Commerce” refers to

Concept: Electronic commerce is any trade conducted over an electronic network. Mobile commerce (m-commerce) is the branch of electronic commerce in which the buyer's access device is a wireless handheld — a mobile phone, feature phone or tablet — that the buyer carries on the person. What such a device adds is ubiquity: the selling business can reach the buyer at whatever place and time the buyer happens to be, instead of waiting for the buyer to sit at a fixed terminal.

Application: Read each listed wording as a candidate meaning of the term and test it against that ubiquity property.

1. Fix the test: a meaning of the term must state something about the channel through which a commercial transaction reaches the customer.

2. Location-independent reach — a business able to reach its potential customers wherever they are — is exactly that channel property, because the handheld device travels with the customer.

3. The term therefore means conducting commercial transactions with customers through wireless handheld devices, which is the wording "the ability of business to reach potential customers wherever they are".

Cross-check: Contrast the remaining wordings by what each one actually names.

• "a myth which does not exist in reality" — this denies existence, yet mobile wallets, m-ticketing and handset banking are live measured channels, so the term names a real category of trade.

• "the ability to have large capacity of memory storage dealing trade and commerce" — this names a storage-hardware property; storage sizes the records a transaction leaves behind and is chosen independently of the device through which the customer transacts.

• "None of the above" — a blanket exclusion cannot hold here, because a listed wording already states the ubiquity property.

Result: M-Commerce (mobile commerce) is the buying and selling of goods and services through wireless handheld devices, and its hallmark is that the business reaches the customer wherever the customer is.