Step 1: Understanding the Concept:
Keyboard shortcuts are used in software applications to perform tasks faster without using a mouse.
Step 2: Detailed Explanation:
1. Create a New document: The shortcut is usually Ctrl + "N" (for New).
2. Save a document: The shortcut is usually Ctrl + "S" (for Save).
3. Undo the last action: The universal shortcut for undoing is Ctrl + "Z".
Step 3: Final Answer:
Matching these results in A-Ctrl+N, B-Ctrl+S, and C-Ctrl+Z, which aligns with option (A).