In phenol coefficient test, higher coefficient value indicates
A. The increased efficiency of the disinfectant
B. The decreased efficiency of the disinfectant
C. The disinfectant does not affect the bacterial growth
D. None of the above

Hint: Phenol is the aromatic organic compound. It is a volatile white crystalline solid. The molecule of phenol consists of one phenyl group and one hydroxyl group.

Complete Answer:
Phenol coefficient test: Phenol coefficient is the number which indicates the effectiveness of a disinfectant as a germicide (which can kill germs) relative to phenol.
- In order to calculate phenol coefficient divide the number indicating the degree of dilution of the disinfectant in which it kills the microorganism within a given time with that of number that indicates the degree of dilution of phenol killing the microorganisms under the same condition and in same period of time.
- A phenol coefficient can be determined by this simple calculation.
- If the phenol coefficient is greater than 1, it means that the disinfectant is more effective than phenol. If the phenol coefficient is less than 1, it means that disinfectant is less effective than phenol.

Hence, the option A is the correct option for this question.

Note: Phenol coefficient can also be defined as the measure of the bactericidal or germicidal activity of a chemical compound in relation with phenol. Germicides have the ability to kill various types of microbes such as bacteria, fungi, viruses, vegetative cells, etc.