Which of the following statements is correct?

When borax is dissolved in water,it gives an alkaline solution. The alkaline solution consists of the following products:

The number of acidic protons in $H_{3}PO_{3}$ is:

Identify the correct statements from the following:
$(a)$ In orthoboric acid, boron is in planar geometry.
$(b)$ In $BCl_3 \cdot NH_3$, boron has tetrahedral geometry.
$(c)$ Aqueous solution of borax is acidic.

Which one is a pseudo alum?

The reaction of $H_{3}N_{3}B_{3}Cl_{3}$ $(A)$ with $LiBH_{4}$ in tetrahydrofuran gives inorganic benzene $(B)$. Further,the reaction of $(A)$ with $(C)$ leads to $H_{3}N_{3}B_{3}(Me)_{3}$. Then,compounds $(B)$ and $(C)$ respectively,are