The geologic time scale is a system of chronological dating that relates geological strata to time, and is used by geologists, paleontologist, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history. Hope I helped!
Answer:
The correct answer is A.
Explanation:
A mutagen changes the level of mutations that occur in the DNA either by affecting it physically or chemically. This helps researchers create different organisms with altered phenotypes according to what the research needs so that the genes can be investigated further under a controlled environment.
So the answer is A.
I hope this helps.
Phosphate, Nitrogen, & Nucleotides
It refers to enzymes and catalysts