The answer is D. The natural selection is a theory which illustrates the gradual process of evolution in the population due to the change of environment. The key point is the mutation (variation) exists in the population before the environment changing. For C, if the environment does not change, though the adaptation is useful to environment, it will not be selected. Because the organisms without the adaptation will not die.
-Headaches, which may be severe and worsen with activity or in the early morning.
-Seizures. People may experience different types of seizures. Certain drugs can help prevent or control them.
-Personality or memory changes.
-Nausea or vomiting.
-Fatigue.
-Drowsiness.
-Sleep problems.
-Memory problems.
Answer:
Option B, a generation
Explanation:
A pedigree is a tree diagram that represents the relationships between different individuals based on certain facts and medical(genetic evolutionary) histories. Basically , the branches of the tree represents the generations which allows the researcher understand how certain genetic characteristics or traits are transmitted with in a family
Such as transmission of any genetic diseases from one generation to the other.
Hence, option B is correct
Prokaryotes. they are the oldest living organisms