The correct answer is -
E. double coincidence of wants
Let "r" stand for the recessive red hair trait. A person with red hair must have a genotype of "rr" ( one from each parent) in order to have red hair( red hair being the phenotype).
Let "B" stand for brown hair and "b" stand for not brown hair. A person with brown hair can have a genotype of "Bb" or "BB" and have a phenotype of Brown hair. This is becasue brown hair "B" is the dominant trait.
It's c because Atoms contain three sub-atomic particles called protons, neutrons and electrons. The protons and neutrons are found in the nucleus at the centre of the atom.
