Answer:
Your answer is C.
Step-by-step explanation:
3.4 μm mean 3.4 Micrometers. Wow, that's pretty small.
A and B can instantly be ruled out, since it's micrometers, which are far smaller than meters. And 1 meter is 1e+6 times bigger than a micrometer, which makes D easily ruled out. The only answer you are left with is C, which is correct.
