A) <u>Mutation</u> is the original source of variations for plants and other organisms which develops differences among their respective species
Explanation:
Genetic variation leads to the natural differences between each individual and among individuals of a species. The main cause for this variation is due to alleles that cause variations in the composition of genes or the DNA sequences.
A mutation is a genetic variation which leads to the creation of a new allele in a species population. Each variation in the DNA sequence leads to an allele formation and each allele leads to a difference in character or trait between individuals since they are the alternate version of the original genes.
Although genetic variations could be brought about by crossing over, random fertilization, or independent assortment; mutation is the original source because it provides the basic raw material for all the evolutionary changes.
Vertebrates have a bilateral symmetry due to which their entire body is divided into right and left halves while the invertebrates either have radial symmetry or the bilateral symmetry. Therefore, option D is correct.
The other basic differences between the vertebrates and the invertebrates are that vertebrates have a spinal cord and a backbone while invertebrates lack them, vertebrates have well developed brain, lungs or gills in respiratory system and closed circulatory system.
Metabolic pathways stimulate cell division.
The answer is: [A]: "A process that cleans pollution from a local pond" .
_____________________________________________________________
Answer: radiation i think
