U $=\{1,2,\{1\},\{2\},\{1,2\}\}$ A $=\{1,2,\{1\}\}$ B $=\{\{1\},\{1,2\}\}$ C $=\{2,\{1\},\{2\}\}.$

Which one of the following sets represents both $($A$)($B$)$ and $($A B$)?$

a$.$

$\{\{1\}\}$

b$.$

$\{,\{\{1\}\}\}$

c$.$

$\{,\{1\}\}$

d$.$

Not one of the above alternatives since $($A$)($B$)($A B$)$