What does this command mean?

$ sort $<$ file$1>$ file$2$

Group of answer choices

It sorts the numbers stored in file$1$ and stores the results into file$2.$

It sorts the numbers stored in file$2$ and stores the results into file$1.$

It sorts the numbers being entered from the keyboard and display the results on console window.

It finds the number between file$1$ and file$2.$