Answer: Option (b) is the correct answer.
Step-by-step explanation:
Viscosity is defined as the property of a liquid that opposes to flow easily or we can say when a liquid resists to flow then it is known as viscosity.
When molecules of a liquid are small then it becomes easy for them to flow whereas when molecules are polar then they tend to form hydrogen bonding which makes the liquid more viscous.
Therefore, small and non-polar molecules would most likely cause a liquid to have the lowest viscosity.