What is the effect of applying bold formatting to text?

Applying bold formatting to text serves the purpose of making it appear darker and more prominent compared to the surrounding text. This effect is often used to draw attention to specific words or phrases, emphasizing their importance in the content. Bold text stands out visually, making it easier for readers to identify key information quickly.

As for the other options, underlining text is a different formatting style entirely and serves a different purpose. Creating bullet points is associated with organizing information rather than enhancing the visibility of text through bold formatting. Increasing the text size also alters the appearance of the text, but it does not specifically relate to the bold style, which focuses on weight rather than size. Therefore, bold formatting clearly enhances readability and highlights essential parts of the text through its darker visual weight.