Assume L$1$ and L$2$ are regular languages defined over the alphabet $\backslash$Sigma

$=\{$a b$\}.$ Which one of the following options concerning statements A$,$ B$,$ and C is correct?

Statement A: L$1*$ is regular.

Statement B: L$1\text{'}$ is not necessarily regular.

Statement C: L$1\backslash$cap L$2$ is regular.

$1.$

Statement A is false.

$2.$

Statement B is false.

$3.$

Statement C is false.

$4.$

All the statements are true.