Quick Styles in MS Word 2010 are pre-built formatting sets available in the Home ribbon's Styles gallery, letting a user format text consistently with a single click instead of manually applying font, size, colour, spacing, etc. Word groups these Quick Styles into a few distinct style types, each of which applies formatting at a different scope within a document.

The four Quick Style types:

• Character styles — Applied only to a selected range of text, which may be as small as a single character or as large as a few words or a phrase within a paragraph. They control purely character-level attributes such as font, size, colour, bold, italic, and underline, and do not touch paragraph-level formatting like alignment, line spacing, or indentation. This is exactly the behaviour described in the question — formatting applied only to selected words/characters within a paragraph, leaving the rest of the paragraph untouched.
• Paragraph styles — Applied to an entire paragraph at once (even if only the cursor is placed inside it, without selecting text). These combine both character formatting and paragraph-level formatting such as alignment, line and paragraph spacing, borders, and indentation — for example, built-in styles like "Heading 1" or "Normal."
• Linked styles — A hybrid type that behaves as a character style if only specific text is selected, but behaves as a paragraph style (affecting the whole paragraph) if no text is selected and the cursor is simply placed within the paragraph. Their behaviour therefore depends on what is currently selected.
• List styles and table styles also exist for formatting bulleted/numbered lists and tables respectively, but "Page styles" as named in this question is not a genuine Word 2010 Quick Style category at all — that terminology instead belongs to other word processors such as LibreOffice/OpenOffice Writer, where "Page Styles" control page-level properties like margins and headers/footers.

Since the question asks specifically for the style type that applies only to selected words or individual characters (never to the whole paragraph), the correct answer is Character styles.

Why the other options don't fit:

• Paragraph styles affect the complete paragraph's formatting, not just selected characters, so they don't match the description.
• Linked styles can behave like a paragraph style too, depending on selection, so they are not restricted to characters only.
• The concept named in the remaining option does not exist as a Quick Style type in Word 2010 at all, ruling it out entirely.