Which describes the correct order of the geologic time scale, from oldest to most recent?

a. mesozoic era - paleozoic era - precambrian time - cenozoic era

b. cenozoic era - paleozoic era - mesozoic era - precambrian time

c. paleozoic era - precambrian time - mesozoic era - cenozoic era

d. precambrian time - paleozoic era - mesozoic era - cenozoic era