Assertion : $\left[\mathrm{B}\left(\mathrm{OH}_2\right)_6\right]^{3+}$ and $\left[\mathrm{B}(\mathrm{OH})_4\right]^{-}$form octahedral and tetrahedral structures. Reason : Being electron deficient, boron readily reacts with Lewis bases like $\mathrm{H}_2 \mathrm{O}, \mathrm{OH}^{-}$ The correct option among the following is

• A

  (A) is true, (R) is true and (R) is the correct explanation for (A)
• B

  (A) is true, (R) is true but (R) is not the correct explanation for (A)
• C

  (A) is true but (R) is false
• Correct answer
  D

  (A) is false but (R) is true

Hence, the correct answer is option: 'D'.