What is Single Sign$-$Off?

Select the correct option$($s$)$ and click submit.

A mechanism of signing off from any application,

A mechanism that enables turning off digital signatures.

A mechanism that enables logging off from $/$ terminates access to multiple 'Single Sign$-$On$\text{'}$ enabled application off from just one of the 'Single Sign$-$On$\text{'}$ enabled application$/$system$.$

None of the above.