The custom.conf file grants sudo privileges to user1 and webadmin for managing the Apache web service, but it uses different commands for each of them. User1 is allowed to use systemctl to start and stop the httpd service, while webadmin is allowed to use init.d, service, or apache2ctl to restart the httpd service. However, the user1 is unable to restart the service, only start and stop it. To fix this, user1 should be able to use the same commands as webadmin, which can be achieved by listing webadmin as a group in the custom.conf file, using the syntax %groupname. This way, user1 will inherit the sudo privileges of the webadmin group, and be able to restart the Apache web service without compromising the least privilege security model.
Reference
Sudo and Sudoers Configuration | Servers for Hackers, section "Groups"
Chapter 12. Managing sudo access - Red Hat Customer Portal, section "12.1. Configuring sudo access for users and groups"

Explanation
The best command to use to transfer the local file accounts.pdf to the remote /tmp directory of the server with the IP address 10.10.10.80 is B. scp accounts.pdf [email protected]:/tmp. This command will use the secure copy protocol (scp) to copy the file from the local machine to the remote server over SSH. The command requires the username and password of the user on the remote server, as well as the full path of the destination directory.
The other commands are either incorrect or not suitable for this task. For example:
A: rsync [email protected]:/tmp accounts.pdf will try to use the rsync command to synchronize files between the local and remote machines, but it has the wrong syntax and order of arguments. The source should come before the destination, and a colon (:) should separate the remote host and path.
C: cp [email protected]:/tmp accounts.pdf will try to use the cp command to copy files, but it does not work over SSH and it has the wrong syntax and order of arguments. The source should come before the destination, and a colon (:) should separate the remote host and path.
D: ssh accounts.pdf [email protected]:/tmp will try to use the ssh command to log into the remote server, but it has the wrong syntax and arguments. The username should come before the remote host, and a file name is not a valid argument for ssh.

The sshd is the Secure Shell Daemon, which is a service that allows remote login to a Linux system using the SSH protocol. The output shows that the sshd is running on port 2222, which is a non-standard port for SSH.
The default port for SSH is 22, which is what the user is trying to use. Therefore, the statement B is most likely causing the issue. The statements A, C, and D are incorrect because they do not explain why the user cannot log on using port 22. References: [How to Change SSH Port in Linux]

Explanation
The vi text editor is a popular and powerful tool for editing text files on Linux systems. The vi editor has two modes: command mode and insert mode. In command mode, the user can issue commands to manipulate the text, such as moving the cursor, deleting, copying, pasting, searching, replacing, and saving. In insert mode, the user can type text into the file. To switch from command mode to insert mode, the user can press various keys, such as i, a, o, I, A, or O. To switch from insert mode to command mode, the user can press the Esc key.
To insert a character at the end of the current line in the vi editor, the user can press the A key in command mode. This will move the cursor to the end of the line and switch to insert mode. Then, the user can type the desired character and press Esc to return to command mode. The statement D is correct.
The statements A, B, C, and E are incorrect because they do not perform the desired task. The p key in command mode will paste the previously copied or deleted text after the cursor. The r key in command mode will replace the character under the cursor with another character. The bb key in command mode will move the cursor back two words. The i key in command mode will switch to insert mode before the cursor. References:
[How to Use vi Text Editor in Linux]