In the wet tests for identification of various cations by precipitation, which transition element cation doesn't belong to group IV in qualitative inorganic analysis?

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : Ketoses give Seliwanoff's test faster than Aldoses.

Reason (R) : Ketoses undergo $$\beta$$-elimination followed by formation of furfural.

In the light of the above statements, choose the correct answer from the options given below :

What is the correct order of acidity of the protons marked $$\mathrm{A}-\mathrm{D}$$ in the given compounds ?

Which of the following is correct order of ligand field strength?