An Organism Grown in Nutrient Rich Broth to High Turbidity

Multiple Choice

An organism grown in nutrient rich broth to high turbidity always produces a blue pigment. When a large inoculum is transferred to a nutrient rich agar plate, it also appears blue. A researcher noticed that this never happens when very small colonies are grown on low nutrient agar plates, however. What is the most plausible conclusion?

A) Large populations enabled the differentiation of a subpopulation of cells that created the blue pigment.
B) Only high nutrient conditions provide enough energy for cells to produce this secondary metabolite that appears blue.
C) Production of the blue pigment production is linked to quorum sensing.
D) The strong gradient from very high to low nutrient bioavailability induces production of the blue metabolite.