The answer is A because it is not formed from decaying marine animals.
The rigth answer is D.
The wavefront or wavefront is an equal phase surface of a wave, i.e., these points have the same travel time from the source. The concept is used to describe the propagation of waves such as sound or electromagnetic radiation (light, radio waves, etc.). In a homogeneous and isotropic medium, in which the waves propagate without deformation, two types of particular waves are distinguished according to whether the wavefronts are spheres (spherical wave) or planes (plane wave).
1 Blue and yellow: 1 yellow
Let us assign the allele for Blue dragon color as B and that of Yellow dragon color as Y and create the punnet square below;
The phenotypic ratio will, therefore, be;
1 Yellow/Blue : 1 Yellow
D-walls and doors would represent the cell membrane