What is Codominance? A. Where both traits are expressed.
B. Where one trait is expressed and the other is hidden.
C. None of the above

A. Where both traits are expressed.

Codominance is a relationship between two versions of a gene. Individuals receive one version of a gene, called an allele, from each parent. If the alleles are different, the dominant allele usually will be expressed, while the effect of the other allele, called recessive, is masked.

Poly-metallic nodules

Explanation: Poly-metallic nodules are generally considered to the manganese nodules, formed due to the accumulation of rocks and mineral aggregates at the seafloor, adjacent to the underwater volcanoes.

This nodules appears in concentric layers, i.e these are the layers of manganese hydroxide and iron hydroxide. They are commonly found at the sea floor and have economical importance.