在shell脚本中,以下哪个命令用于打印变量的值?
A. var_dump
B. echo
C. ls
D. env
以下哪条命令将执行脚本并退出shell?
A. run
B. source
C. ./
D. exec
以下哪条命令将等待用户输入并将用户输入保存到变量中?
A. exec
B. get
C. read
D. prompt
以下能正确定义一个shell函数的是?
A. Parentheses to declare the function (optional) and curly braces to contain the commands
B. Curly braces to declare the function and parentheses to contain the commands
C. Square brackets to declare the function and curly braces to contain the commands
D. Run quotes to denote the function