Answer:
The correct answer is case control study.
Explanation:
A study in which a comparison is made between the patients carrying the disease with the patients not carrying the disease is known as the case-control study. In the mentioned study, the one carrying the disease is termed as cases, and the one that does not possess the disease is termed as controls.
This form of study is generally done to predict the association between the disease and the risk factor. In case-control studies, only observation is done as no attempt is made to change the course of the condition. The prime objective of the study is to predict the exposure of the risk elements for the individuals present in two groups, that is, controls and cases. This form of study is also called case-referent studies or retrospective studies.
I think tracheae which is B not sure tho
Answer:
The species that develop in aquatic environments, need to be able to have an adequate locomotion and according to the hydrostatic pressure in the water, which this pressure has the opposite direction to gravity in terrestrial life.
Explanation:
Vertebrates that have a skeleton are accustomed to gravitational forces, and this bone structure is what allows adequate locomotion to perform movements as a function of the force of earth's gravity, in water the force of gravity has no effect, since that the hydrostatic force predominates, which the direction is opposite to the gravitational forces.
Amorphous bodies, with few solid structures, not bony, make them better adapt to movements in water masses that are promoted by hydrostatic forces.