The spacing at the start of a paragraph is called:

The correct answer is Indentation.

• Indentation refers to the blank space inserted from the margin to the beginning of a line or paragraph. It is commonly used to visually separate paragraphs or create hierarchical structures in text.
• Line Spacing (A) is the vertical distance between lines of text.
• Margin (B) is the space between the edge of the page and the main text block.
• Justification (D) refers to how text is aligned along the left and right margins, such as left-justified, right-justified, centered, or full-justified.

Therefore, the spacing specifically at the start of a paragraph is known as indentation.