Scientists have never seen the ancient horses shown in figure 16-4 what do you think was the main type of evidence scientists used to prepare these diagrams

It is likely that scientists used fossil evidence to prepare these diagrams. Even if a complete fossil of a particular species is never found, a critical mass of fossil evidence can reveal a lot of information. Even a single key leg bone can provide a good idea of the physiological form and size of that individual animal. Continual fossil discoveries and debate amongst paleontologists will begin to develop a consensus of what the species likely looked like.

answer: the answer is b

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.