What term should be added to $y^2-\frac{1}{5}y$ to make it a perfect square trinomial?

A) 5
B) $\frac{1}{100}$
C) 100
D) $\frac{5}{2}$
E) $\frac{1}{50}$

Simplify and collect like terms: 4(a² - 3a - 4) - 2(5a² - a - 6)