<span>amount of nitrogen, oxygen, and other elements dissolved in the water. Hope this helps!</span>
Default network
When the brain is unoccupied, an fMRI indicates that blood continues to flow via a web of brain regions called the default network.
The default network is a web of brain regions that have activity that corresponds greatly with each other and different from other networks within the brain. The default network is active when an individual's attention is not concentrated on the external environment and it is measured with the functional magnetic resonance imaging technique (fMRI).
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.
What is Mutation
The major source of the genetic diversity among microorganisms upon which natural selection operates is Mutation.
Hope this help
plz mark brainliest
HAVE A NICE DAY!!!
