Correct Option
The Assertion states that Phenyl is used as a household germicide. This is correct. Phenyl is a widely employed disinfectant for general household sanitation, effective against a broad spectrum of bacteria and other microorganisms.
The Reason states that Phenyl is a phenol derivative and phenol is an effective germicide. This is also correct. Phenyl formulations typically contain cresols (methylphenols) or other phenolic compounds, which are derivatives of phenol (C₆H₅OH). Phenol itself is a potent antiseptic and disinfectant, known for its ability to denature proteins and disrupt microbial cell membranes, thereby killing microorganisms.
The Reason correctly explains the Assertion. The germicidal action of phenyl as a household product is directly attributable to its chemical composition, which includes phenol derivatives that retain the disinfectant properties of phenol.
Incorrect Options
Option 2 is incorrect because the Reason provides a direct and accurate explanation for the Assertion. The germicidal nature of phenyl is a consequence of its derivation from phenol, a known germicide.
Option 3 is incorrect because the Reason is factually true. Phenyl compounds are indeed derived from phenol, and phenol is an effective germicide.
Option 4 is incorrect because the Assertion is factually true. Phenyl is commonly used as a household germicide.