An electron micrograph shows a prokaryotic cell with a diameter of $1\,\mu\text{m}$ at a magnification of $50\,000$ times. What is the cell diameter in the electron micrograph?
- A$5 \times 10^{-1}\,\text{mm}$
- B$5 \times 10^{0}\,\text{mm}$
- C$5 \times 10^{1}\,\text{mm}$
- D$5 \times 10^{2}\,\text{mm}$