The answer is; E
This shows that these organelles were once free-living organisms with their own mechanisms for reproduction which they have retained even after years of symbiotic relationship with the higher organisms. During their duplication, they also replicate their own DNA. Their DNA does not have histones (as opposed to the DNA in the nucleus of their host eukaryotic cell) similar to that of simple organisms such as bacteria.
Humans usually have 46 chromosomes. Monkeys, chimps, or other organisms related closely to them: they have diploid number of 48 chromosomes.
(Future reference: Haploid means half, half the # of chromosomes in the nucleus. Diploids means duplicate, COMPLETE necessary set of chromosomes).
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