Scientists developed a new margarine containing plant ingredients they think will lower blood cholesterol levels in people who use the margarine. they want to test this by comparing the cholesterol levels of people who use the new margarine for a while to cholesterol levels of a group of people who use regular margarine. this is an example of what type of research design? a. intervention studyb. epidemiological study

a. Intervention study

Explanation:

In an interventional research study the participants receive an intervention as they are given a new item or commodity to use and the results of use are evaluated on the basis of change made by the commodity on the participant. Such studies are used for the purpose of clinical trails.  

The given research design is the example of interventional study. As the margarine is a new commodity the ingredients of which are claimed to lower down the blood cholesterol levels which can tested by comparing the cholesterol levels in people.

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).