Wich of the following is most affected by drought and flood

Analyze the question: We need the mode of transport that depends most directly on water levels, since drought means too little water and flood means too much.

Explain the concept:

• Drought lowers water levels in rivers. Channels become shallow, sandbars appear, and boats and barges can't pass or must carry lighter loads.
• Flood raises water levels and increases flow speed. It can wash away landing jetties and make navigation dangerous. Floating debris and strong currents also disrupt movement.
• Inland waterways like the Niger and Benue rivers in Nigeria are seasonal. Navigation is good in the rainy season but poor in the dry season, and flooding can disrupt it at peak rainfall.

Step-by-step evaluation:

• A. Ocean transport: The sea is huge and deep, so its level isn't noticeably changed by drought or local floods. Ships are only affected by storms, not these events.
• B. Road transport: Floods can damage roads and bridges, but drought barely affects roads. So it's affected mostly by only one of the two.
• C. Air transport: Aircraft fly above both conditions, and are mainly affected by weather like fog, storms, and poor visibility.
• D. River transport: Affected by both. Drought makes rivers too shallow, and flood makes them dangerous and unpredictable. This is the best fit.

Answer: D, river transport.

Exam tip: When a question mentions both drought and flood, look for the option that depends directly on water volume. Rivers fit because their level rises and falls with rainfall. Remember: "Rivers rise and fall with rain, so river transport rises and falls with it too."