Good quiz. Two seemed a little tricky to me because I wasn't sure that they had deltas. Hasn't the USA so used up the waters of the Colarado for irrigation that it fails to reach the ocean at all? It is certainly true that the Okavango doesn't reach the Ocean. Are you saying that the Okavango swamp is a kind of internal (inland) delta?
yeah, in most years the Colorado river no longer reaches the ocean, but there is still the remains of a delta there. Also, the current river ends up in Mexico in a sort of delta-shaped place with a lot of subdividing channels.The Okavango delta is delta shaped and often referred to as a delta, even though it doesn't reach the ocean. Despite the fact that it doesn't, it's still geologically an alluvial delta. I would consider the alluvial fans in the Mojave Desert deltas even though they don't reach the ocean.