请阅读下列代码，①、②、③、④处的输出结果依次是？（  ）

class Fruit:
    price=０
    def __init__(self):
         self.color='red'
         country="China"
if __name__=="__main__":
    print(Fruit.price)  #①
    apple=Fruit()
  print(apple.color)  #②
  Fruit.price=Fruit.price+15
  print( "apple's price:"+str(apple.price))  #③
  banana=Fruit()
  print ("banana's price:"+str(banana.price))  #④