<span>Genes are the main cause of a Carabelli Cusp.
This is a condition where there is an additional cusp on the first molar of the
tooth and become less pronounce when progressing to the second and third
molars. In some cases, the cusps' forms included pits, ridges, and furrows. <span>
<span>The Carabelli
Cusp is a condition most common in Europeans and rarest in the Pacific Islands.
It is an inherited feature from a homozygote or a heterozygote gene that can be
present or absent in some
individuals. It was
discovered in the year 1842 by Georg Carabelli, a court dentist of the Austrian
Emperor Franz. </span></span></span>
Tissue culture is the growth in an artificial medium of cells derived from living tissue.
D is the best option, that's the part that absorbes food and water
