Which of the following statements is not true?

• A
  The spin magnetic moment of $KO_2$ is $1.73 \ BM$
• B
  The hybridization of $B$ in $H_3BO_3$ is $sp^2$
• C
  In $H_2S_2O_8$,$S-S$ linkage is present
• D
  In $ClF_3$,axial and equatorial bonds are not identical