The correct answer is A. pg.
The pg command is used to view a text file one page at a time. The -n option can be used to specify the number of lines per page. For example, to view a file 24 lines at a time, you would use the following command:
pg -n 24 myfile.txt
The cat command is used to concatenate and print the contents of a file to standard output. The -n option can be used to specify the number of lines per page. However, the cat command does not pause after each page, so you will need to press Enter to continue viewing the file.
The lp command is used to print a file. The -n option can be used to specify the number of copies to print. However, the lp command does not view the file, it only prints it.
The /p option is not a valid option for any of the commands listed.
Therefore, the correct answer is A. pg.