I want to know the answer to the following question:
What was notable about the discovered vitamin A?
All the background I'm provided with is that "In 1913, Elmer McCollum discovered the first vitamins, fat-soluble vitamin A, and water-soluble vitamin B (in 1915; now known to be a complex of several water-soluble vitamins) and named vitamin C as the then-unknown substance preventing scurvy.". Is that enough to answer the question?
Answer: yes