Let r₁ and r₂ be the radii of the largest and smallest circles, respectively, which pass through the point (-4,1) and having their centres on the circumference of the circle x² + y² + 2x + 4y – 4 = 0. If r¹/r² = a+b√2, then a + b is equal to:
a) 3
b) 11
c) 5
d) 7
