Question

Which two keys she used to copy a file/folder

Answer 1

The keys used are ctrl + c to Copy

Answer 2

She used CTRL + C at the same time to copy the file.
First, select the file by clicking the the right click once & then press the both keys.
This will not prompt you anything. But, by presing the keys the file will be copied and go the directory where you want to paste it.
You can do it manually selecting the options & also can do the same by using CTRL + V command.