C is the answer just did it
<em>here is the answer ,, you can make a decay curve like this example..</em>
Answer: Possession of Valves
Explanation: Veins possess valves which ensures that blood flows in only one direction. Valves helps blood to flow back to the heart against gravitational force.
Arteries don't have valves because the pressure originating from the heart is capable of causing the blood to flow in one direction.
The 4 factors affect evolution, according to Darwin’s Origin
of Species are;
Variation
Heritability
Competition
Differential survival
Variation ensures that
there is variability of population traits
on which selection pressures will apply.
Heritability means that the traits must be able to be passed down to offsprings through gametes.
Competition occurs when the individuals in the population compete for limited resources
Differential survival
occurs due to competition for resources
and other selection pressures. This result
to the survival of the strongest and weeding
out of the weak from the population.