DNA (or deoxyribonucleic acid) is the molecule that carries the genetic information in all cellular forms of life and some viruses. It belongs to a class of molecules called the nucleic acids, which are polynucleotides - that is, long chains of nucleotides.
The answer is IgA.
IgA is the immunoglobulin that consists of a dimer or a tetramer, a J-chain polypeptide, and a polypeptide chain called the secretory component. IgA is the principal antibody class in the secretions that bathe the mucosal surfaces, acts as an important first line of defense. It is also an important serum immunoglobulin, mediates a variety of protective functions through interaction with specific receptors and immune mediators.
Increased carbon dioxide levels
This is because the plant takes in Carbon Dioxide to use it's carbons to help make energy. So if there is more carbon dioxide, there is more photosynthesis going on in the plant since carbon is also in the sugar the plant uses.
Two different species are most likely to evolve from one ancestral species allopatrically, after the ancestral species has split into two populations.