Select the most appropriate meaning of the given idiom.

Rank and file

Ordinary workers in a company

The most appropriate meaning of the idiom "rank and file" is ordinary workers in a company.

The other options are incorrect.

• "The manager of a personnel department" is not the same as rank and file. The manager of a personnel department is a member of management, while rank and file refers to the ordinary workers.
• "Financial activities in a firm" is not the same as rank and file. Financial activities refer to the way a company manages its money, while rank and file refers to the ordinary workers.
• "A very well-organised company" is not the same as rank and file. A well-organized company can have both ordinary workers and managers.

The idiom "rank and file" comes from the military, where it refers to the ordinary soldiers. It is used in a general sense to refer to the ordinary members of any group or organization. So, when someone says that they are speaking for the rank and file, they mean that they are speaking for the ordinary members of the group or organization.