Which of the following is not a characteristic of Wadis?

Analyze the question: We need the option that is NOT a characteristic of wadis.

Concept: A wadi is a dry river valley or channel found in desert and semi-arid regions (common in the Sahara, Arabia, and the Middle East). It stays dry for most of the year. It only carries water briefly after rare, heavy rainfall, which often causes flash floods.

Step-by-step evaluation:

• A. They are river channels: True. A wadi is a channel or valley cut by running water, even though it is usually dry.
• B. They occur in tropical areas: True. Wadis occur in hot desert regions, many of which lie in or near the tropics (for example, the Sahara around the Tropic of Cancer).
• C. They hold permanent streams: False. Wadis are dry most of the time and have only temporary, seasonal streams after rain. They do not hold permanent streams.
• D. They have steep craggy walls: True. Sudden flash floods cut deep, steep-sided valleys.

Answer: The option that is not a characteristic of wadis is C.

Exam tip: Remember "Wadi = Wet only When it's rainy." Whenever you see "permanent" or "perennial" linked to a desert feature, be suspicious. Desert streams are ephemeral (temporary), not permanent.