Statement-$1$: Orthoboric acid acts as a weak monobasic acid in water.
Statement-$2$: Orthoboric acid acts as a proton donor in water.

• A
  Statement-$1$ is true,Statement-$2$ is true. Statement-$2$ is the correct explanation for Statement-$1$.
• B
  Statement-$1$ is true,Statement-$2$ is true. Statement-$2$ is not the correct explanation for Statement-$1$.
• C
  Statement-$1$ is true,Statement-$2$ is false.
• D
  Statement-$1$ is false,Statement-$2$ is true.