Dispersion patterns of organisms are dependent on the scale used to measure them. For example, goldfish in a tank are clamped if you look using the scale of a whole house, but evenly distributed at the scale of the tank itself. An example of animals that are likely to be clamped at a large scale, but uniformly distributed at a small scale is:

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

youre right there are

the offspring would all be white. if the parents are both white flowers then they have the genotype rr, which when crossed results in an all white punnet square.