The following system is consistent when

$not{p}^{{?}^{?}}r$

$p^{{?}^{?}}q$

$(pr)vvq$

Select one:

a$.$ The system is inconsistent

b$.p=$ False, $q=$ True, $r=$ True

c$.p=$ True, $q=$ True, $r=$ True

d$.p=$ False, $q=$ False, $r=$ True