Data gets lost from the main memory when power is switched off: This is correct because the main memory (RAM) is volatile memory, meaning it requires power to retain data. When the computer is turned off, any data stored in RAM is lost.

Main memory is slower than the secondary memory: This is incorrect. In fact, main memory (RAM) is much faster than secondary memory (like hard drives or SSDs).

Main memory is very inexpensive memory: This is incorrect. Main memory (RAM) is relatively expensive compared to secondary memory.

The Shift key on a keyboard is used to change the case of characters from lowercase to uppercase (or vice versa). Holding down the Shift key while pressing a letter key will produce an uppercase letter if the Caps Lock is off.

In Microsoft Word and many other applications, pressing Ctrl + F opens the Find feature, which allows you to search for specific text within the document.

The other shortcuts serve different purposes:

• Ctrl + A: Selects all the text in the document.
• Ctrl + H: Opens the Find and Replace dialog, allowing you to search and replace text.
• Ctrl + S: Saves the document.

Therefore, to search for text in a Word document, you would use Ctrl + F.

A web browser is a software application specifically designed to allow users to view, retrieve, and interact with webpages on the Internet. Examples include Google Chrome, Mozilla Firefox, Microsoft Edge, and Safari.

MS-Office is a productivity software suite developed by Microsoft that includes applications like Word, Excel, PowerPoint, and Outlook. It is not an operating system.

The other options are all examples of operating systems:

• Android: A mobile operating system developed by Google.
• Linux: An open-source operating system used in various devices, from computers to servers.
• Microsoft Windows: A popular desktop operating system developed by Microsoft.

Therefore, MS-Office is not an operating system.