For Reliable Results,the Niacin Test Should Be Performed Only from Cultures

Multiple Choice

For reliable results,the niacin test should be performed only from cultures that are at least:

A) 2 weeks old and show at least five colonies on Löwenstein-Jensen medium.
B) 3 weeks old and show at least 50 colonies on Löwenstein-Jensen medium.
C) 3 weeks old and show at least 50 colonies on Middlebrook 7H11 agar.
D) 2 weeks old and show at least five colonies on Middlebrook 7H11 agar.