What is the rate of change of temperature inside the earth?

1. Temperature decreases at the rate of 1°C for every 32 metres of descent.
2. Temperature increases at the rate of 1°C for every 32 metres of descent.
3. Temperature remains constant
4. Temperature decreases at the rate of 32°C for every 1 metre of descent.

Temperature increases at the rate of 1°C for every 32 metres of descent.