Common descent is referred to as a theory because
A) there is overwhelming evidence to support it from many areas of biology.
B) scientists are reasonably sure it's true, but there's little evidence to support it.
C) it's an idea from more than 100 years ago and thus is not a modern idea.
D) it's the only idea about life on Earth that can be tested by observation of the material universe.

Question

Quizplus · Accepted Answer

Common descent is considered a theory in biology because there is overwhelming evidence from many different areas of study that support it, such as molecular biology, paleontology, and comparative anatomy. It is a well-established idea, and while new evidence may refine our understanding of it, there is little doubt among scientists that it is true.

Common Descent Is Referred to as a Theory Because