Consider the following sets:

$($a$)$

A $=\{\backslash$alpha $,\backslash$beta $,\backslash$gamma $\}$

B $=\{$a$,$ b$\}$

Which of the following ordered pairs cannot belong to B $\backslash$times A$?$:

$($i$)($a$,\backslash$alpha $)$

$($ii$)($a$,$ a$)$

$($iii$)($a$,\backslash$gamma $)$

$($iv$)(\backslash$beta $,$ a$)$

$($v$)($b$,\backslash$beta $)$

$($vi$)(\backslash$gamma $,$ a$)$