The maternal effect in Lymnaea is such that the genotype of the egg determines the direction of shell coiling regardless of the genotype of the offspring. Apparently, the cause of this spectacular maternal effect results from ________.

A) orientation of the spindle apparatus in early cleavage
B) genophores present in the egg cytoplasm
C) the F factor exerting its influence on the centrosome
D) colicins "poisoning" one of the cleavage centers
E) allelic substitution as demonstrated from RNA injection experiments