Thioglycolate Medium Contains the Following: Yeast Extract, Pancreatic Digest of Casein

Thioglycolate medium contains the following: yeast extract, pancreatic digest of casein, glucose, L-cysteine, sodium chloride, sodium thioglycolate, and agar.It is considered a complex medium because

A) depending on their oxygen utilization pattern, organisms will grow differently on it.
B) it has multiple ingredients for a broad range of nutrients.
C) both yeast extract and pancreatic digest of casein are not chemically defined.
D) thioglycolate has a carbon-sulfur bond that many microbes cannot break enzymatically.