According to IS4031 (Part 5), the set time of cement is measured at

• A. Room temperature and humidity
• B. 25-29 degree C and 90-100% Rel. humidity
• C. 23-27 degree C and 95% Rel. humidity
• D. 25-29 degree C and 60-70% Rel. humidity
• E. 25-30 degree C and 65% Rel. humidity