Your network contains a server that has Microsoft SharePoint Foundation 2010 installed.
You need to back up the server farm configuration.
The solution must minimize the size of the backup.

What should you select from Backup and Restore in Central Administration?

A.
From Granular Backup, click Export a site or list.

B.
From Granular Backup, click Perform a site collection backup.

C.
From Farm Backup and Restore, click Perform a backup.

D.
From Farm Backup and Restore, click Configure backup settings.

Explanation:
From Central Administration -> Backup and Restore -> Farm Backup and Restore, click Perform a Backup:

On this page, components to be included in the farm backup are selected.
A description of each component is included in the right-hand column.

Select the components to be backed up, then click Next.

Source: http://community.bamboosolutions.com/blogs/sharepoint-2010/archive/2010/12/03/sharepoint-2010-cookbook-backing-up-data-part-1-farm-backup.aspx