Consider the following hypothesis:

soil type affects the germination of radish seeds.

which of these should the experiment do in order to best test this hypothesis?

a.
measure the rate at which radish plants grow after their seeds germinate

b.
measure the average depth at which germinating radish seeds were planted

c.
compare the percentages of radish seeds that germinate in different types of soil

d.
compare the average numbers of radish seeds that germinate in different states