I think its b i hope am right
Explanation:
Since Charles found that the volume is directly proportional to temperature when the mass and pressure remain constant this means that with increase in temperature, there will be increase in volume.
Mathematically, 
at constant Pressure
This equation represents the relationship in Charles' law.
You can't have a carrier with a dominant pedigree because other wise than individual or organism would be afflicted by the gene and render them incapable of being a carrier. A carrier is an individual/organism that has a normal phenotype (meaning it is not afflicted by said gene) but is carrying the gene that could cause disease or whatever the affect may be. In this case the gene would have to be homozygous recessive to be expressed. Hopefully this helps!
Answer:
Population.
Explanation:
Population may be defined as the smallest unit of ecology and the evolution might occur at the population level.
Population is the group of the organisms that belong to the particular species and lives in a specific particular habitat. The individual of the population breeds among themselves. Sometimes the individual of two different population can also breed among themselves in extreme cases.
Thus, the answer is population.
A controlled variable is not changed throughout an experiment. It is there so that the other variables being tested on can be better understood.
