The correct temperature setting of the iron for thermal curling is determined by the _____.

• A. length of hair
• B. texture of the hair
• C. color of hair
• D. density of hair

Answer: (B)

Texture determines how hair responds to heat, so it guides the appropriate iron temperature for thermal curling. Finer hair heats up and damages more easily, so a lower temperature protects the cuticle while still helping the curl set. Coarser hair has a tougher cuticle and can tolerate higher heat, which helps activate and hold the curl. Medium texture falls in between, requiring a moderate setting. While color and density can influence heat dynamics slightly—color can affect absorption and density can affect how heat distributes—they are not the primary factor. Length isn’t the main predictor either. So, texture is the best indicator for choosing the correct temperature.