In a RAO model, which stands for Responsible, Accountable, Consulted, and Informed, the accountable role must be assigned to only one individual. The accountable role is the person who has the ultimate authority and responsibility for the outcome of the project or task, and who approves or rejects the work done by the responsible role. The accountable role cannot be delegated or shared, as it is essential to have a clear and single point of accountability for each project or task.
The other roles can be assigned to more than one individual:
* Responsible. This is the person who does the work or performs the task. There can be multiple responsible roles for different aspects or phases of a project or task, as long as they are coordinated and supervised by the accountable role.
* Informed. This is the person who needs to be notified or updated about the progress or results of the project or task. There can be multiple informed roles who have an interest or stake in the project or task, but who do not need to be consulted or involved in the decision-making process.
* Consulted. This is the person who provides input, feedback, or advice on the project or task. There can be multiple consulted roles who have expertise or experience relevant to the project or task, but who do not have the authority or responsibility to approve or reject the work done by the responsible role.

The best recommendation to mitigate the risk of data leakage from lost or stolen devices that contain confidential data is to configure them to auto-wipe after multiple failed access attempts, as this would prevent unauthorized access and erase sensitive information from the device. Requiring employees to attend security awareness training, password protecting critical data files, or enabling device auto-lock function are also good practices, but they may not be sufficient or effective in preventing data leakage from lost or stolen devices.
References: CISA Review Manual (Digital Version), Chapter 5, Section 5.3