​Carbon isotope dating is useful in studying the history of life because ____.

A) ​the ratio of ¹⁴C to ¹²C in living organisms changed at key geological events
B) ​12C decays at a set rate based on a set time scale
C) ​14C is incorporated into fossil remains only
D) ​carbon is only incorporated into living organisms
E) carbon is lost uniformly once an organism dies

Carbon Isotope

Carbon isotopes are variants of carbon atoms that differ in the number of neutrons, notably carbon-12, carbon-13, and carbon-14, where the latter is often used in radiocarbon dating to determine the age of archaeological samples.

Geological Events

Natural occurrences such as earthquakes, volcanic eruptions, and plate tectonics that shape the earth's surface and environment.

Living Organisms

Entities that exhibit the characteristics of life, such as growth, reproduction, and the ability to respond to their environment.