Split the second term in 3a^2 - 8a + 4 into two terms
3a^2 - 2a - 6a + 4 = 0
Factor out common terms in the first two terms, then in the last two terms.
a(3a - 2) -2(3a - 2) = 0
Factor out the common term 3a - 2
(3a - 2)(a - 2) = 0
Solve for a;
a = 2/3,2
Answer : B. (2/3,2)