What is the biggest desert in the world? A) Gobi Desert B) Arabian Desert C) Gibson Desert D) Sahara Desert

What the question is really asking

You are choosing which option names the largest desert from the list. Even though Antarctica is the largest desert overall (a cold desert), it is not one of the answer choices, so we compare only the four listed deserts.

Comparing the sizes of the options

• Sahara Desert: about $9.2\text{ million km}^2$ (North Africa)
• Arabian Desert: about $2.3\text{ million km}^2$ (Arabian Peninsula)
• Gobi Desert: about $1.3\text{ million km}^2$ (Mongolia and northern China)
• Gibson Desert: about $0.156\text{ million km}^2$ (Australia)

Picking the correct choice

The Sahara is far larger than the Arabian, Gobi, and Gibson deserts, so the correct answer is D) Sahara Desert.