某文本型字段的值只为字母且不允许超过4个,则可将该字段的输入掩码属性定义为( )。
A.AAAA
B.LLLL
C.CCCC
D.####
参考答案:B
______ you are in trouble, let me know. I'll give you a hand. [ ]
A. Whenever
B. Wherever
C. However
D. Whatever