The mismatched combinations are

A. Chlorophyll - Co

B. Water hardness - EDTA

C. Photography $-\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]^{-}$

D. Wilkinson catalyst $-\left[\left(\mathrm{Ph}_{3} \mathrm{P}\right)_{3} \mathrm{RhCl}\right]$

E. Chelating ligand - D-Penicillamine

Choose the correct answer from the options given below :

Let's analyze each combination : <br/><br/> A. Chlorophyll - Co : Mismatched. Chlorophyll has a magnesium (Mg) ion at its center, not cobalt (Co). <br/><br/> B. Water hardness - EDTA : Correct match. EDTA (ethylenediaminetetraacetic acid) is used to treat water hardness by chelating metal ions like Ca²⁺ and Mg²⁺. <br/><br/> C. Photography - [Ag(CN)₂]⁻ : Mismatched. Silver halides (AgX, where X = Cl, Br, I) are used in photography, not [Ag(CN)₂]⁻. <br/><br/> D. Wilkinson catalyst - [(Ph₃P)₃RhCl] : Correct match. Wilkinson's catalyst is a homogeneous hydrogenation catalyst with the formula [(Ph₃P)₃RhCl]. <br/><br/> E. Chelating ligand - D-Penicillamine : Correct match. D-Penicillamine is a chelating agent that can bind to metal ions through multiple coordination sites. <br/><br/> The mismatched combinations are A and C. So, the correct answer is : <br/><br/> A and C Only.