Answer:
D
explain: The Move from high concentration to low competition. Until the concentration is equal . Diffusion expand needs no energy
According to the CDC, tooth decay
affects more than one-fourth of U.S. children aged 2 to 5.Tooth decay is the
damage of the structure of the tooth which is caused by acids that are produced
when sugar is being broken down by plaque bacteria in the mouth. Tooth decay is the primary cause of tooth loss in children in the United
States.
Mono you can not get mono through drinking water and it’s a disease
Answer:
D.) Helpful variations allow individuals to survive and reproduce better than members who lack these variations.
Explanation:
Variation is one of among the principles of natural selection.
Variations occur naturally thereby favouring some individual groups over the other.
In the above example, the helpful variations naturally select the parents of the offsprings while the other members of the group are disadvantaged.