The correct answer is - A. Death rate.
We get the fertility rate from the birth rate and the death rate. More specifically, from the number of the children that are born in a given time frame (usually a year) we minus the number of the people that have died in the same time frame, so the difference between them gives us the fertility rate.
The fertility rate can be positive (in the difference is a positive number) and negative (if the difference is negative number).
Hey there! Darwin's finches had different beak sizes and shapes because of natural selection. Over time, the more desirable traits become more dominant and distinct. These beaks were best fit for the type of food the bird ate. Smaller-beaked birds usually have a seed diet, and larger-beaked birds usually eat large nuts or small creatures like worms and bugs. Hope this helps!
➜ Fission (binary and multiple), regeneration and fragmentation are considered as methods of asexual reproduction because all of them involve only one parent and gametes are not formed in them. New individuals produced after cell division are always genetically identical or clone to their parents.