Federal Accounting relating to taxing?

Sally is a cash basis taxpayer and a member of the Valley Barter club. This year Sally provided 100 hours of sewing services to the barter club in exchange for two football playoff tickets. Which of the following is a true statement?

1.Sally need not recognize any gross income unless she sells the football tickets.

2.Sally's exchange does not result in taxable income.

3.Sally is taxed on the value of the football tickets even if she cannot attend the game.

4.Sally is taxed on the value of her sewing services only if she is a professional seamstress.

5.All of these are true.

I chose the second answer and that was wrong, the 3rd answer is the correct one. Anyone care to explain this one to me before I confront this to my teacher? thanks in advance.