Using an electron micrograph of an animal cell with a magnification of $\times 9600$, a student measured the width of a mitochondrion. The measured width on the micrograph was $6\ \text{mm}$. What was the actual width of the mitochondrion?
- A$6\ \mu\text{m}$
- B$0.6\ \mu\text{m}$
- C$0.06\ \mu\text{m}$
- D$0.006\ \mu\text{m}$