There is one extra 21 comosome which is why it is down sydrome.
The most complex cellular organization is actually the organisms but since its not on the choices its the organs.
A hot spot is here magma appears near to the surface. Imagine this, the crust is a plate, and the hotspot is a pencil, as the plate moves, you punch holes through the plate. This is the hotspot creating volcanoes as the crust moves. This is how hotspot volcanoes are created. The volcanoes that are created on boundaries are created from differences in the crust as it is created.
