Which of the statements about anhydrous aluminium chloride is correct

Assertion : Coloured cations can be identified by borax bead test.

Reason : Transparent bead $(NaBO_2 + B_2O_3)$ forms coloured bead with coloured cation.

Three pairs of compounds are given below. Identify that compound in each of the pairs which has group $-13$ element in more stable oxidation state. Give reason for your choice. State the nature of bonding also. $(A)$ $TlCl_3, TlCl$ $(B)$ $AlCl, AlCl$ $(C)$ $InCl_3, InCl$

Give uses of boron and its compound. 

In some of the reactions thallium resembles aluminium, whereas in others it resembles with group $-I$ metals. Support this statement by giving some evidences.