True or False: Maternal Effect on Snails

True statements:
2) Martha's genotype cannot be DD. (her mother must be dd, so her genotype cannot be DD)
4) All Martha's brothers must be sinistral. (all siblings are affected due to maternal effect, both male and female)

1  is wrong because she could be Dd and still exhibit the condition due to maternal effect (Martha's *mother* must  be dd).
3 is incorrect because although her mother is dd, her mother's mother could have been Dd, and thusly Martha's mother would have been unaffected due to maternal effect.
5 is false because if Martha's father is DD, Martha will be Dd, and therefore her offspring will be unaffected, again, due to maternal effect.