An electrical signal is shown on a cathode-ray oscilloscope (c.r.o.). The time-base is adjusted to $50\,\text{ms div}^{-1}$. The Y-gain is adjusted to $2\,\text{V div}^{-1}$. What is the amplitude of the signal?
- A$2\,\text{V}$
- B$4\,\text{V}$
- C$5\,\text{V}$
- D$10\,\text{V}$