Select the statements that are true considering the output of the command below:

$\backslash$table$[[tcp,0,00\mathrm{.}0\mathrm{.}0\mathrm{.}0$:$22,0\mathrm{.}0\mathrm{.}0\mathrm{.}0$:$**,$LISTEN$],[$tcp$,0,0127*0\mathrm{.}0\mathrm{.}53$:$53,0\mathrm{.}0\mathrm{.}0\mathrm{.}0$:$**,$LISTEN$],[tcp,0,0127*0*0\mathrm{.}1$:$631,0\mathrm{.}0\mathrm{.}0\mathrm{.}0$:$***,$IISTEN$],[cp6,0,0$:::$80,$:::${?}^{***},$LISTEN$],[$p $6,0,0$:::$21,$:::${?}^{***},$LISTEN$],[cp6,0,0$:::$22,$:::${?}^{***},$LISTEN$],[p6,0,0$::$1$:$631,$: : : $*,$LISTEN$]]$

a$.$ There is a SSH server running.

b$.$ The port $80$ accepts only IPv$6$ communications.

c$.$ The ports $21$ and $22$ shown are udp.

d$.$ The ports $21,22,$ and $80$ are in use.

e$.$ Apache is installed and listening on port $80.$