下列各种形式的循环中，输出“*”的个数最少的循环是

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