The fact that the two strands of DNA are complementary <span />
The correct answer is B !! Both are interdependent thus forming a mutualistic association !!
As both can not live without each other thus making obligate !!
so They share obligate mutual association !! Go with B !!
no because Separation of oxygenated and deoxygenated blood in the heart of three types of animals. The three-chambered frog heart mixes oxygenated and deoxygenated blood in the ventricle. Therefore, the body never receives fully oxygen-rich blood.
Answer: D volcanic eruption