Some multiple choice questions of Computer Science: Linux command;

Actually I can google it but the choice here is a little..unclear. So I can't make sure..Thank you!

1:What does the Linux command cat do?

a. copy the contents of a file to the screen

b. count the number of characters in a file

c. create a Linux catalog

d. open up an edit session allowing you to modify a file

2:Which of the following Linux commands is best for getting help on the syntax and format of a Linux command?

a. grep

b. rm -r

c. ls -l

d. man

3:The linux command >

a. redirects the output of a command into a file

b. compares two files to see which one is larger

c. does nothing. > is NOT a linux command.

d. compares two files and displays all the differences

Thank You!