Samira is developing a virtual private chat application for ABC Consulting. The following are requirements provided by the organization while making the application: $1.$ All the communications should happen within the same network, host$-$to$-$host. $2.$ The information shared through this app should be kept confidential. Hence, the whole IP packet should be encrypted, giving access to only authorized personnel. $3.$ There should be a private network for host$-$to$-$host communication Which of the following modes should Sara consider for encryption in this project?