A student researching the Sahara Desert has taken the following notes:
• The Sahara is the world's largest hot desert, spanning 3.6 million square miles • Temperatures can exceed 130°F during the day and drop below freezing at night • The Sahara was once green and supported lakes approximately 10,000 years ago • Desertification continues to expand the desert's southern edges • Nomadic peoples have crossed the Sahara for trade for millennia
The student wants to explain how the Sahara has changed over time. Which choice most effectively uses relevant information from the notes?
The Sahara is the world's largest hot desert, spanning 3.6 million square miles.
The Sahara's extreme temperatures can exceed 130°F by day and drop below freezing at night.
The Sahara has transformed dramatically—from a green landscape with lakes 10,000 years ago to today's desert, which continues expanding through desertification.
Nomadic peoples have crossed the Sahara Desert for trade for millennia.
Correct Answer: C
Choice C. From green with lakes to expanding desert shows change over time.