The Cambrian Period is a time in Earth history when ____________.
A)the first abundant shelly organisms appear in the fossil record
B)Earth's interior was so hot that a solid outer crust,if present,was likely being extensively remelted
C)stable continental interiors,termed cratons,first formed
D)the dinosaurs appeared and came to dominate large-scale terrestrial life

Question

Quizplus · Accepted Answer

The Cambrian Period is known for the sudden appearance of abundant shelly organisms in the fossil record, representing the diversification of life during this time. Choices B, C, and D are not accurate descriptions of the Cambrian Period.

The Cambrian Period Is a Time in Earth History When