Question

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.

Answer 1

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 would provide the most support for the proposition that the composition of ocean water has remained constant for thousands of years. This statement directly supports the idea that the composition of ocean water has not changed over time, as the salt deposits that were formed in the past have the same composition as those formed today. The other statements provide supporting evidence but not as strong as statement A.