I'm going to say B because the other answers just don't seem to make sense.
Answer:
skin appendages and physio-chemical properties
Explanation:
skin appendages can redirect and or stop the absorption of the drug as well as the physio-chemical properties of the drug itself that make it harder for the skin to absorb
It’s a scalar value that can be computed from the elements of a square matrix and encodes certain properties of the linear transformation
