A. Internet ads
B. Newspaper ads
C. TV commercials
D. Radio ads
Those are the options you have given, so first, internet commercials are cheap, and some let you advertise for free. Newspaper ads only charge you around $20 per week, or less. TV commercials are most expensive because you have to do some animation, and the commercial normally has to last around 15 seconds. Advertising via radio is also cheap. Your answer would be C!