(A) Gutter margin
(B) Bottom margin
(C) Left margin
(D) Indent margin
🧠 Explanation:
The margin added to the binding side while printing is known as the gutter margin. This extra space ensures that text or content near the binding edge remains fully visible and isn’t obscured when the document is bound, such as in books, booklets, or multi-page reports, allowing for comfortable reading and professional presentation.