Final answer:
The correct term for folders contained within other folders is 'subfolders,' which can also be referred to as 'nested folders' or 'child folders.'
Step-by-step explanation:
Folders contained within other folders are referred to as subfolders. This is a common term used in file management systems whether on a computer or in a cloud storage environment. For example, if you have a main folder titled 'Work' and inside it, you have another folder named 'Reports', the 'Reports' folder is considered a subfolder of the 'Work' folder. It's also known as a nested folder or a child folder, but not a parent folder because the parent is the main, or top-level, folder that contains one or more subfolders within it.