A Venn diagram can be used to compare and contrast nucleic acids.
RNA
DNA
Which characteristic would be correctly found in B?
contain ribose
consist of two strands
made of nucleotides
have an R group

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.

  eukaryotic cells may arise from sexual reproductions, resulting in more genetic variation  i would say that is the answer

See how growing plants react to different conditions of light, temperature, or carbon dioxide concentration.