Crowdsourcing describes:

a. how the input of many people can be leveraged to make decisions that used to be based on the input of only a few people.

b. how the level of buzz created for a product can be used as a measurable parameter for determining the product's effectiveness.

c. the methods in which a consumer should use a product or service.

d. the need for consumers to buy a product and their willingness to buy it.