The list below shows some events which took place at different periods in the geologic time scale. 1. fish with craniums appear. 2. mammals appear. 3. sharks appear. which of these best orders the events from the earliest to the most recent? select one: a. 1, 2, 3 b. 1, 3, 2 c. 2, 1, 3 d. 2, 3, 1

Answer is B) 1, 3, 2

Fish with craniums naturally preceded the evolution of sharks, since sharks have craniums. Sharks must have evolved from a cranium-wielding ancestor. 
Sharks evolved about 450 million years ago, before land vertebrates (animals with spines and skeletal systems) even existed. Mammals evolved about 100 million years later. 

The answer is c) tons