What are two internal factors that organisms respond to?

Researchers randomly divide participants into groups. each group takes a different amount of omega-3 fatty acid supplements daily for a month. one group receives a placebo. the researchers measure the impact on cholesterol levels in the blood. what is the purpose of random assignment in this experiment? a, to produce treatment groups with similar characteristics b, to ensure that all people with high cholesterol have an equal chance of being selected for the study c, to increase the accuracy of the research results and prevent skewness in the data

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )

Idon’t know the answer and i’ve been stuck on it for a while now skskskskks