Which of the following is a false statement?

Question

$\begin{array}{1 1}(a)\;\text{Bond order is inversely proportional to the bond length}\\(b)\;\text{As bond order increases the strength of the bond increases}\\(c)\;\text{ Bond order is proportional to the bond length}\\(d)\;\text{(d) Molecules with negative bond order are highly unstable}\end{array}$