An estuary is where salt water and fresh water meet. Estuaries are usually found at the edge of the coast, where the ocean water, or salty water, meets river, lake, any fresh water source, water.
A tributary is something completely different. It is a, usually smaller than the main river or lake, river/stream stemming off a bigger river or lake, or flowing into that river or lake.
I think c is the Dead Sea, so A is your best guess
We do not know what you mean by that, can you add a picture or something?
Adolf hitler hated the French
S wave is the type of seismic wave that travels only through solids. The correct option among all the options that are given in the question is the third option or option "c". It is also known as Shear wave or Secondary wave and are actually a type of elastic wave that moves through the body of an object.