Jasilyn is conducting market research for a new product idea. She has decided that direct marketing to consumers is easier and is sending online ads directly to her potential customer list via online mail. She also wants to be able to track which potential customers are opening the ads and which are just deleting them unopened. What type of marketing approach is Jasilyn using?

A.
online advertising

B.
search engine optimization

C.
social media marketing

D.
email marketing