GitHub supports various syntax formats that align with Markdown and HTML conventions. Here's a breakdown of the provided options:

Comment Syntax:

Option Cis correct. The syntaxis used in Markdown files to insert comments. These comments will not be rendered in the final output, making them useful for adding notes or instructions within the code or documentation.

Incorrect Options:

Option A(* This is a heading) is incorrect because an asterisk (*) denotes an unordered list item, not a heading. A heading in Markdown is typically created with one or more hash symbols (#).

Option B(This is a link) is incorrect because this is plain text and not the syntax for creating a link. The correct syntax would be[This is a link](URL).

Option D(This is bolded text) is incorrect because this is plain text, not the correct Markdown syntax for bold text, which should be**This is bolded text**or__This is bolded text__.

Option E(1. This is an ordered list) is incorrect as it does represent an ordered list item, but it was not the syntax format asked about in the question. The question specifically focuses on matching associated text with syntax, where only the comment option is correct.

References:

GitHub Flavored Markdown (GFM)

GitHub Docs: Basic writing and formatting syntax

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