What is the factored form of a2 – 121?
(a – 121)(a – 1)
(a – 11)(a + 11)
(a + 11)(a + 11)
(a – 121)(a + 1)
(a – 121)(a – 1)
(a – 11)(a + 11)
(a + 11)(a + 11)
(a – 121)(a + 1)