The diagram illustrates a thermometer marked in degrees Celsius. What are the readings of the lower fixed point and the upper fixed point on the Celsius scale?
- Alower fixed point -10 ^{\circ}C, upper fixed point 110 ^{\circ}C
- Blower fixed point 0 ^{\circ}C, upper fixed point 20 ^{\circ}C
- Clower fixed point 0 ^{\circ}C, upper fixed point 100 ^{\circ}C
- Dlower fixed point 20 ^{\circ}C, upper fixed point 100 ^{\circ}C