Strength of DTPA extract used for micronutrient analysis is

Answer: Option C

The strength of DTPA extract used for micronutrient analysis is 0.005M.
DTPA (Diethylene triamine Penta acetate) micronutrient extraction method is a non-equilibrium extraction for estimating the potential soil availability of Zn, Cu, Mn and Fe. It has been used for cadmium, nickel and lead in soils.
The soils are extracted for available cationic micronutrients using the AB-DTPA method developed by Soltanpour and Workman in one set and by DTPA extracting solution (0.005 M DTPA, 0.1 M triethanolamine, 0.01 M Cacl₂).