Step 1: Concept
Dihydroxy derivatives of benzene have specific common names based on the relative positions of the $-\text{OH}$ groups.
Step 2: Identification
- 1,2-diol: Catechol
- 1,3-diol: Resorcinol
- 1,4-diol: Quinol (or Hydroquinone)
Step 3: Conclusion
Benzene-1,4-diol is commonly known as Quinol.
Final Answer: (C)