A team of biologists develop a new drug, and one team member hypothesizes that the drug is incapable of freely passing across the plasma membrane and requires the help of membrane proteins to enter cells. Alternatively, another biologist on the team hypothesizes that the drug can diffuse passively across the plasma membrane like O2 and CO2 can. Which of the following, if true about the drug, best supports the alternative hypothesis that the new drug will exhibit simple diffusion across plasma membranes?
a. The drug is a small non-goiar moleaule.
b. The drug is a small charged moleoue.
c. The drug is a large polar molecule.
d. The drug is a large charged molecule.