Loyal consumers have found numerous uses for WD$-40$ lubricating spray beyond what its manufacturer intended. For example, some people use the product as an insect killing spray. A few years ago, its manufacturer ran a contest asking people to send in ways that they used the product. By capitalizing on the unforeseen ways its product gets used, the WD$-40$ manufacturer could implement a strategy.

Select one:

a$.$ market penetration

b$.$ market development

c$.$ product development

d$.$ diversification

e$.$ product penetration