Name the conventional solvent that was used for dry cleaning purposes which later confirmed to be a suspected carcinogen.

Name the conventional solvent that was used for dry cleaning purposes which later confirmed to be a suspected carcinogen.
 
(a) Supercritical CO2
 
(b) Phenanthrene
 
(c) Tetrachloroethene
 
(d) Benzene aldehyde
 
I had been asked this question in an interview for internship.
 
This intriguing question comes from Green Chemistry topic in division Environmental Chemistry of Chemistry – Class 11
Select the correct answer from above options 
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