Q$.30$ What are the counting states $(Q_1,Q_2)$ for the counter shown in the figure below?

$($a$)01,10,11,00,01.$

$($b$)11,10,00,11,10$dots

$($c$)00,11,01,10,00$

$($d$)01,10,00,01,10$

$[$EC GATE$-2009]$