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