Early formulations of this medium used a smaller amount of carbohydrate and occasionally produced false (pink) results after 48 hours. this phenomenon is called a reversion.

Inoculate a PR broth is a medium that used smaller amount of carbohydrate and may result to occasionally false pink after 48 hours. It is known to have slow growing fermenter that may indicate false negativity and also poor sensitivity with the result of the test.

so whats the answer

the answer is c on e2020, bud.