If you can use any letters, it would have to be 2 lower case letters such as tt
Answer Internal and external environmental factors, like gender and temperature, influence gene expression. ... Similarly, drugs, chemicals, temperature, and light are among the external environmental factors that can determine which genes are turned on and off, thereby influencing the way an organism develops and functions.
Explanation:
The correct answer is Sideways.
The theory of common descent states that all living organisms are descendants of a single ancestor. Phylogenetic trees and cladograms are often used to hypothesize the evolution of various organisms and shared common descent.
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