What describes a compliant balloon?

• A. Ability to grow rapidly as more pressure is applied and continue until balloon ruptures
• B. Maintains constant size under pressure
• C. Has a fixed inflation limit
• D. Constricts under pressure

Answer: (A)

Balloon compliance describes how a balloon’s size changes as you inflate it. A compliant balloon expands readily with increasing pressure, its material stretching so the diameter grows as more air or liquid is added, and it can continue to enlarge until it eventually ruptures if overinflated. That behavior—rapid growth with pressure and no fixed limit until rupture—is the hallmark of a compliant balloon.

This is why the statement about expanding as pressure rises and continuing to enlarge until rupture best fits a compliant balloon. The other ideas describe noncompliant behavior (maintaining constant size or having a fixed inflation limit) or an action (constricting under pressure) that doesn’t occur with a balloon under typical inflation.