Which metal ion gives a violet bead in the borax bead test?

Match List-$I$ with List-$II$ and choose the correct answer from the options given below:

List-$I$ (Name of the test)	List-$II$ (Reaction sequence involved) [$M$ is metal]
$A$. Borax bead test	$I$. $MCO_3$ $\rightarrow MO$ $\xrightarrow[+\Delta]{Co(NO_3)_2} CoO \cdot MO$
$B$. Charcoal cavity test	$II$. $MCO_3$ $\rightarrow MCl_2$ $\rightarrow M^{2+}$
$C$. Cobalt nitrate test	$III$. $MSO_4$ $\xrightarrow[\Delta]{Na_2B_4O_7} M(BO_2)_2$ $\rightarrow MBO_2$ $\rightarrow M$
$D$. Flame test	$IV$. $MSO_4$ $\xrightarrow[\Delta]{Na_2CO_3} MCO_3$ $\rightarrow MO$ $\rightarrow M$

What is microcosmic salt?

Which of the following solid salt on heating with solid $K_2Cr_2O_7$ and conc. $H_2SO_4$ evolves orange-red vapours that turn an aqueous $NaOH$ solution yellow?

Which salt is used during the bead test in the qualitative analysis of inorganic substances?

Which of the following salts is used in the bead test for the qualitative analysis of inorganic substances?