Answer:
b.digital marketing
Explanation:
According to my research, in 2019 it is calculated that about 88% of young adults aged 14-22 years old own a cellphone. This being the case, the smartest direct marketing to choose would be "digital marketing". This is because it will reach the vast majority of the 14-22 year old demographic as well as given them the ability to respond instantly to the time sensitive offers through their internet connected devices.
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