I don’t understand the question but if I can make a correct inference, they have thorns to protect themselves from predators.
Answer:
True breeding
Explanation:
True breeding is a breeding in which parents produce the offspring which carry same phenotype.
The parents in true breeding are homozygous for every trait.
<u>True breeding occurs in the plants when the plants produce offspring of same variety only when self pollination takes place. </u>
<u>For example, if a plant has purple flowers will produce only seeds which will grow into plants which have purple flowers.</u>
The answer is reproductive isolation. Reproductive isolation ensures members of different species do not produce offspring. In this case, geographical separation is ensuring that individuals from the two different populations are not able to mate with each other. Eventually, through different selective pressures, the two populations will diverge sufficiently in genotype to become distinctly different.
Natural selection is the right answer hope this helps.