The false statement among the following is

A) Both BeO and ${\mathrm{Al}}_2{\mathrm{O}}_3$ are amphoteric since the electronegativities of Be(1.5) and Al(1.5) are same and also due to the polarizing powers of ${\mathrm{Be}}^{2+} \mathrm{and} {\mathrm{Al}}^{3+}$ are nearly same BeO and ${\mathrm{Al}}_2{\mathrm{O}}_3$ should have equal amphoteric character, but due to more charge density on ${\mathrm{Al}}^{3+}$ it has little more acidic character than ${\mathrm{Be}}^{2+}$ pKa values of ${\mathrm{Be}}^{2+}$ and ${\mathrm{Al}}^{3+}$ are 6.2 and 5.0 respectively. 

B) As the electropositive character of the element decrease. The acidic character of their hydroxides increase

3) $N{a}_2{B}_4{O}_7.10H_{2}O\to \underset{glassbead}{\underbrace{2NaB{O}_2+B_2{O}_3}}+10H_{2}O$