In computer keyboards, the Ctrl, Shift and Alt keys are commonly known as which type of special keys?

Introduction / Context:
In basic computer awareness and competitive exam questions, you are often asked to identify different types of keys on a standard keyboard. The Ctrl, Shift and Alt keys do not usually type characters by themselves, yet they are very important for shortcuts and special commands. This question checks whether you know the correct technical term used to describe this category of keys on a keyboard.

Given Data / Assumptions:

• We are talking about a standard computer keyboard layout used with desktop and laptop computers.
• Specific keys mentioned are Ctrl, Shift and Alt.
• We need to identify the correct category name for these keys from the options provided.
• Assume general operating systems such as Windows, macOS or Linux desktop environments.

Concept / Approach:
Keyboard keys are usually grouped into categories such as alphanumeric keys, function keys, numeric keypad keys, cursor or navigation keys and modifier keys. Alphanumeric keys type letters and numbers. Function keys are the row from F1 to F12 and are used for special actions. Navigation keys move the cursor. Modifier keys are held down in combination with other keys to modify the meaning of the keystroke. Ctrl, Shift and Alt are classic examples of modifier keys used in shortcuts like Ctrl plus C for copy or Ctrl plus S for save. Therefore, we should look for the option that names them as modifier keys.

Step-by-Step Solution:

Verification / Alternative check:
Open any software help page or operating system documentation that lists keyboard shortcuts. You will see references like Press and hold the Ctrl key, Press Shift and use the arrow keys, or Use Alt with other keys to access menu commands. These descriptions make it clear that these keys do not act alone but modify other keystrokes. Technical articles on keyboard design and game configuration also label Ctrl, Shift and Alt as modifier keys, reinforcing that this is the accepted term. This cross check confirms that Modifier keys is the accurate answer.

Why Other Options Are Wrong:

• Function keys: These are F1 to F12, used for tasks like help, refresh or special commands, not Ctrl, Shift and Alt.
• Alphanumeric keys: These are keys that type letters and numbers such as A to Z and 0 to 9, which is not the role of Ctrl, Shift and Alt.
• Adjustment keys: This is not a standard category in keyboard terminology and does not have a precise meaning here.
• Navigation keys: These include arrow keys, Page Up, Page Down, Home and End, which move the cursor or scroll the screen.

Common Pitfalls:
Some learners loosely think of any special key as a function key, but in technical language function keys are the F1 series only. Others may not know the specific term modifier keys and may guess based on everyday language like adjustment keys. To avoid confusion, remember that a modifier key is one that modifies another key. Whenever you press two keys together like Ctrl plus X or Shift plus arrow, the first key in the combination is usually a modifier key. Ctrl, Shift and Alt are the classic examples taught in computer courses.

Final Answer:
Crtl, Shift and Alt on a keyboard are called Modifier keys.