In the spectrofluorimetric determination in solution

A. absorbance of analyte solution is kept near to 0.05

B. oxygen is eradicated from the solution

C. pH of the solution is controlled

D. wavelength of incident light is always above 400 nm

The correct statements from the above is

Concept:-

Spectrofluorimetry is a technique to find out the emission of light when a substance absorbs electromagnetic radiation.

The amount of light absorbed by the metal complexes and the metal ion that they are made of are frequently different.
The stability of metal complexes are determined by calculating the change in absorbance.

According to Beer's Law:-

,

where A= absorbance of light, 

 = molar extinction coefficient,

c= sample concentration and l= optical path length of a sample

Explanation:-

• Spectrophotometer uses a wide range of light i.e. from UV range(185-400nm), Visible(400-700), and IR(700-15000nm).
• It is sensitive to pH, oxygen
• The limit of absorbance of a spectrophotometer is from 0.1 to 1

Conclusion:-

Therefore, The correct statements from the above are A, B, and C.