∵ the central angle of the sector where the first prize is located is 45+45 2 =32× 45,

while the first prize, second prize and third prize * * * occupy 361, and the first prize will be won if you get a 11% discount,

∴ the probability that you can get a 11% discount by rotating the turntable once. 45 361 = 316,

so C. 。