What is the purpose of THHN insulation and what is a common temperature rating used in industrial wiring?

• A. THHN insulation provides ceramic shielding; common rating is 60°C
• B. THHN provides thermoplastic insulation with poor heat resistance; common rating is 75°C
• C. THHN provides thermoplastic insulation with good heat resistance; common rating is 90°C
• D. THHN insulation is a magnetic shielding layer; common rating is 100°C

Answer: (C)