Using a microscope that magnifies 40,000 times, a bacterium is seen to have a length of 5 cm. If a virus is seen to have a length of 2 mm using this microscope, then the ratio of its actual size to its enlarged size will be:

• A. 8000
• B. \(\frac{1}{{4000}}m\)
• C. 5 × 10-5m
• D. 2.5 × 10-5