Niger and Congo are two rivers after which countries are named (actually in both cases two countries each) - and those are African countries, so they must be in Africa.
Zambezi is a river in Angola and Namibia.
Tigris is a River in Mesopotamia, in Asia - so that's the correct answer!
Most electricity is generated using energy.
Speaking from experience, the answer is not D.
I reckon Birds, cause they are everywhere in Australia and there a heaps of different types.
