Viral marketing is a kind of marketing method in which the originator sends the initial information of the product to the user and then relies on the user's initiative to carry out word-of-mouth propaganda. This strategy is like a virus, using rapid replication of information to thousands, even millions of audiences.
According to the above definition, which of the following is viral marketing?
After a business uses the advertisement word of originality propaganda, the netizen retransmits makes it quickly become catchword.