Factor the Trinomial Completely $a r ^ { 2 } - 12 a r + 11 a$

Multiple Choice

Factor the trinomial completely. $a r ^ { 2 } - 12 a r + 11 a$

A) $a ( r - 11 ) ( r + 1 )$
B) $a ( r - 11 ) ( r - 1 )$
C) $a ( r + 11 ) ( r - 1 )$
D) $( a r - 11 a ) ( r - 1 )$
E) not factorable