The answer to this question is B
Toxicity is a chemical property
The plant belongs to the group Angiosperm. Vascular plants with seeds could be cycads, Gingko, conifers, or angiosperms. Among those groups, only angiosperms have flowers.
The plant they found have colored, scented flowers which suggests that it could be pollinated by insects or birds. Colored flowers attract birds and insects. Color serves as a guiding mark. Talking of scent, it does not attract bird, but attracts insects. It also serves as the guiding mark.
Hm, I thought it would be 0%. . . Since the male (hetero) would be Bb and the female (homo dominant) would be BB, So the dominant gene would be dominant over all of the recessive genes. (BB, BB, BB, Bb).
The respiratory system contains the lungs, so the answer is C. Hope this helps.