A security analyst enters grep OS updates.txt into the command line. What does this tell the operating system to do?

Tools of the Trade: Linux and SQL | Weekly challenge 3 Quiz | 

A security analyst enters grep OS updates.txt into the command line. What does this tell the operating system to do?

• Move the updates.txt file to the OS directory
• Create a new directory named OS and a new file named updates.txt
• Search through the updates.txt file and return all lines containing the string OS
• Create a new file named updates.txt in the OS directory