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