Answer:
D. The first 50 people to see the show get a free band T-shirt and a free CD!
Option D provides a clear incentive for people to attend the show. Offering a free band T-shirt and a free CD to the first 50 people who attend the show is a tangible benefit that people can receive by coming to see the band perform. This incentive is likely to be more effective in attracting people to the show than simply stating that the band "sounds like nothing you have ever heard before" or claiming that the crowd will be huge. While those statements may be true, they don't offer a clear and immediate benefit to people who attend the show.