Both are characterized by low rainfall.
Explanation
A desert is an arid region characterized by extremely high or low temperatures and scarce vegetation. The fundamental defining feature of any desert ecosystem, whether hot or cold, is low precipitation (aridity).
Analysis of Options:
- Both are hot deserts. is Incorrect: The Sahara is a hot desert located in Africa, whereas Ladakh is a cold desert located in the Himalayas (India). They differ significantly in their temperature ranges.
- Both have dense vegetation. is Incorrect: Due to extreme climatic conditions and lack of water, both regions possess scanty or sparse vegetation. They do not support dense vegetation.
- Both are characterized by low rainfall. is Correct: The common characteristic defining both as deserts is low rainfall. This aridity limits plant growth and defines the landscape in both regions.
- Both are located in Africa. is Incorrect: The Sahara Desert is located in the continent of Africa, while Ladakh is located in Asia (India).
Key Takeaway:
Deserts are primarily defined by aridity (low rainfall) and sparse vegetation, irrespective of whether they are hot or cold in terms of temperature.