在Visual Basic中,下列循环程序段输出“*”的个数最小的是( )
A、a = 5: b = 8 Do Print "*" a = a + 1 Loop While a < b
B、a = 5: b = 8 Do Print "*" a = a + 1 Loop Until a < b
C、a = 5: b = 8 Do Until a>b Print "*" b = b + 1 Loop
D、a = 5: b = 8 Do Until a>b Print "*" a = a + 1 Loop