The answer is phenolics. Milady states it directly: "Tuberculocidal disinfectants..., often referred to as phenolics, are proven to kill the bacterium that causes tuberculosis." Phenolics are one of the stronger disinfectant classes used in barbershops specifically because they're effective against TB, a bacterium that's notably harder to kill than most.
Quats — the other named disinfectant class on this question — are common and effective for everyday sanitation, but aren't the tuberculocidal category; nonpathogenic and infectious are general terms, not disinfectant classifications at all, and don't belong in the same category as this question's actual answer choices.
Milady Standard Barbering, 6th ed., Ch. 4 (Infection Control), p. 60: "Tuberculocidal disinfectants..., often referred to as phenolics, are proven to kill the bacterium that causes tuberculosis."
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