The correct options are
C The higher slopes of the Himalayas experience snowfall.
D The Northern Plains experience an average temperature of 10-15 degrees Celsius.
Temperatures are generally low during both days and nights. The average temperature rises as we move from north to south. The higher slopes of the Himalayas experience snowfall. The Northern Plains experience an average temperature of 10-15 degrees Celsius, while down south, near Chennai, it is around 24-25 degrees Celsius.