Respuesta :
Answer:
The answer is D. An observational study
Step-by-step explanation:
The researchers are observing how different diets in the cattle affects their body composition. They are not counting a population or anything so it is not a census. It is not a sample survey because they aren't asking cows and it is not an experiment because they are not changing or testing anything. They are just viewing meaning it is an observational study.
your answer is D. Observational Study on 3dgenuity