Why is tranpiration also called a necessary evil

What claim did thorne make? what evidence supported his claim?

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

I’m doing some practice exam questions for biology, and i’m not sure how to do these 3 parts to the question.