The equation of a circle is x2 + y2 + 6x + 4y + 10 = 1. What is this equation written in its standard form?

A) (x + 3)2 + (y + 2)2 = 4
B) (x + 6)2 + (y + 4)2 = 4
C) (x + 6)2 + (y + 4)2 = 10
D) (x + 3)2 + (y + 2)2 = 10