The Deepest Area on Planet Earth

This question, as it stands, is pretty meaningless. What do you mean by "the deepest area"?

You can, in theory, go down almost 4,000 miles into the Earth. The deepest area of all is the centre of the planet's core – even if, strictly speaking, this is "in" the Earth rather than "on" it.

Fortunately, as this is a quiz and most of us have heard this question once or twice before, we would probably assume that it's referring to the deepest part of the oceans – or what Wikipedia refers to as "the deepest known point in the Earth's seabed hydrosphere (the oceans)."

And fortunately, we'd be right.