What is an allele? trait form that is hidden by a dominant gene identical copies of two different genes trait form that is displayed by recessive genes one of different forms of the same gene

one of different forms of the same gene.

Explanation:

Mendelian ‘factor’ later called genes. The gene is responsible for the inheritance of traits or characteristics. The genes for each present in different forms. Each organism have two copies of each gene for a trait. For example, the shape of a seed is determined by the gene R its allele will be r. Thus, alternative forms of a same gene is called allele. Round seed is dominant have genes RR or Rr. Wrinkled seed is recessive feature  will be rr.  

it's c. (to reduce the greenhouse effect/carbon gasses)