A) reproduction process has inbuilt tendency for variation .error in DNA copying during reproduction cause variations and result into variety of organisms.
b)i)In asexual reproduction offspring are more similar as it is monoparental . Genetic material only one parent is involved which result into less variation and more similarity
ii) in sexual reproduction organism are not much similar as it is biparental process and genetic material of two individual is involved.
c)evolution leads to formation of two different species which is caused by genetic drift, natural selection,geographical isolation and severe change in DNA of germ cell. Its is usually caused when there is geographical isolation in above case and result into species which cannot interbreed.