Please hurry

Consider the proposition below.
The composition of ocean water has
remained constant for thousands of
years.
If the following statements are true,
which one provides the most support for
this proposition?
A Salt deposits that were formed
thousands of years ago by the
evaporation of ocean water have the
same composition as salt deposits
formed today.
B The composition of salt deposits formed
by the evaporation of ocean water is
similar everywhere in the world.
C The shells of marine animals that
lived thousands of years ago have
the same composition as the shells of
marine animals that live today.
D The types of marine animals living
in different parts of the world have
stayed the same for thousands of years.