单选题：In Linux, command“command1 || command2 ” means ?

In Linux, command“command1 || command2 ” means ?@[A](1)
A. command2 will be executed if command1 returns nonzero
B. command2 will be executed if command1 returns zero
C. command1 and command2 will be executed concurrently
D. command1 and command2 will be executed sequentially




A.command2 will be executed if command1 returns nonzero
B.command2 will be executed if command1 returns zero
C.command1 and command2 will be executed concurrently
D.command1 and command2 will be executed sequentially


答案：A