Answer:

Explanation:
The relation between frequency and wavelength is shown below as:
c is the speed of light having value
Given, Wavelength = 188 μm
Also, 1 μm =
nm
So,
Wavelength =
m
Thus, Frequency is:

D) reacts with oxygen
All other are physical properties.
I think the answer you have selected is right, I'm not sure tho