A
They cannot synthesize certain vitamins themselves and depend on the insects digested by them.
B
They have remained in that particular stage of evolution as living fossils, a link between autotrophs and heterotrophs.
C
Their growth in shady and dark places does not allow them to understake sufficient photosynthesis and thus they depend on insects for nutrition.
D
They are adapted to grow in nitrogen deficient soils and thus depend on insects for sufficient nitrogenous nutrition.
