The answer is (C)
ΔABC and ΔBDE are two equilateral triangle. D is the midpoint of BC.
BD = DC = 1/2BC
Let each side of triangle be 2a.
As, ΔABC ~ ΔBDE
∴ Area(ΔABC)/Area(ΔBDE) = AB2/BD2 = (2a)2/(a)2 = 4a2/a2 = 4/1 = 4:1
Hence, the answer is (C).