In MS Word, bold shortcut is:

Text formatting is essential for creating readable and visually appealing documents in MS Word. Applying 'bold' formatting makes selected text appear thicker and darker, drawing attention to important words or phrases. Keyboard shortcuts provide a quick way to apply or remove such formatting without using the mouse. The shortcut for applying bold formatting is straightforward and widely recognized.

• Ctrl + B is the correct shortcut for applying or removing bold formatting to selected text in MS Word. The 'B' directly stands for 'Bold'.
• Ctrl + I is incorrect; this shortcut is used for 'Italic' formatting, which slants text.
• Ctrl + U is incorrect; this shortcut is for 'Underline' formatting, which places a line beneath text.
• Ctrl + E is incorrect; this shortcut is used for 'Center alignment', which centers the selected text or paragraph.