Which of the Following Scenarios Are Free from Bias

Multiple Choice

Which of the following scenarios are free from bias?

A) A scientist is conducting an experiment on liver disease that is funded by a university, and has set up the experiment as a double-blind study testing of a new medication.
B) A scientist is conducting an experiment on liver disease that is funded by a pharmaceutical company, and has set up the experiment as a double-blind study testing of a new medication.
C) A scientist is conducting an experiment on liver disease that is funded by a university, and has set up the experiment study testing of a new medication and only give the medicine to the healthiest patitents.
D) A scientist is conducting an experiment on liver disease that is funded by a pharmaceutical company, and has set up the experiment as a double-blind study testing of a new medication on people without liver disease as well as those with liver disease.