Which factors during meiosis provide the most genetic diversity? a)spindle fiber structure in the sister chromatids b) retention of two sister chromatids in the daughter cells c) crossing over and two possible positions of each homologous pair d) haploid nuclei formation and cytoplasm division during cytokinesis

During crossing over exchange of genes are going on. 
So, answer is 
C) Crossing over and two possible positions of each homologous pair.

The gens present in the dna in the nucleus of the cell in the body

Mitochondria is the cell organelle that produced the energy that is needed in the body system in form of atp, that is why it is called the power house of the cell. energy is needed by the living organisms to carry out the activities which sustain life.  if the mitochondria is destroyed atp will not be produced. if the mitochondria is destroyed, energy production will stop and the affected living organism will not have the energy to carry out the necessary life processes; this will lead to the death of the organism.