The default line spacing in MS Word is 1.15. This means that there is a slight space between each line of text, making it easier to read and visually appealing. Let's break down the answer in detail:

Default Line Spacing:
The default line spacing refers to the spacing between each line of text in a document. It determines the amount of vertical space between lines and affects the overall appearance and readability of the document.

Importance of Line Spacing:
Line spacing is an important aspect of formatting text in a document. It helps in improving readability by providing enough space between lines, making it easier for the reader to distinguish between different lines of text. Line spacing also plays a vital role in making the document visually appealing and organized.

Options in MS Word:
MS Word provides various options for line spacing. These options include single spacing, double spacing, 1.5 line spacing, and others. However, the default line spacing in MS Word is set to 1.15.

Reasoning for Default Line Spacing:
The default line spacing of 1.15 in MS Word is chosen based on readability and aesthetics. It strikes a balance between single spacing, which can appear too compact, and double spacing, which can result in excessive vertical space between lines.

Benefits of 1.15 Line Spacing:
1. Improved Readability: The slight space between lines enhances legibility, especially for lengthy documents or paragraphs.
2. Visual Appeal: The extra space between lines makes the text look more organized and visually appealing.
3. Accommodates Font Styles: Different font styles and sizes may require additional spacing between lines to ensure optimal readability.

Conclusion:
In summary, the default line spacing in MS Word is set to 1.15. This choice is made to ensure improved readability, visual appeal, and compatibility with different font styles. However, users can always change the line spacing according to their preference and specific document requirements.