<span> C - nitrogen fixation, ammonification and nitrification </span>
D. Cones
Cycads are basically composed of woody plants which have roots, a stem, leaves and reproductive structures called Cones. These cones differ from each other depending on the plant whether it is female or male. These cones vary from shape, size, color, etc. based on the sex of the plant.
Answer:
A polygenic trait can be described as a physical trait which is influenced by more than one gene.
The three types of selection for a polygenic trait are:
1) Directional Selection: In a directional selection, one of the phenotype is favored in an ecosystem. As a result of this favoring, the allelic frequency changes and shifts in favor of this particular trait.
2) Stabilizing selection: It is a type of natural selection in which the intermediate trait is favored. The population carries a middle trait in abundance.
3) Disruptive Selection: Disruptive trait is a type of natural selection in which the traits on the extreme sides are favored. The intermediate traits are less favored.