How can clamp() be used to keep font-size between 14px and 20px with a preferred value of 2.5vw?

• A. font-size: clamp(20px, 2.5vw, 14px);
• B. font-size: clamp(14px, 0, 20px);
• C. font-size: clamp(14px, 2.5vw, 20px);
• D. font-size: clamp(12px, 3vw, 18px);

Answer: (C)

Clamp makes a value fluid with a safety net: it uses the preferred value if it lies between the two bounds, otherwise it falls back to the nearest bound. Here, you want the font size to stay between 14px and 20px, while using 2.5vw as the responsive, preferred value. So the right form is font-size: clamp(14px, 2.5vw, 20px). This means the font size will grow or shrink with the viewport (thanks to 2.5vw) but never go below 14px or above 20px.

The other forms don’t fit the requirement: swapping the min and max (min is 20px, max is 14px) breaks the logic; using 0 as the preferred value ignores the desired 2.5vw; and using 12px with 18px max sets different bounds than requested and can still differ from 14–20px.