Which of the following best supports the endosymbiont theory that present-day eukaryotic cells are descendants of a successful symbiotic relationship between a host cell and an engulfed prokaryote? chloroplasts and mitochondria replicate in a similar manner as some prokaryotes. chloroplasts are necessary for photosynthesis reactions in plant and bacteria cells. mitochondria and chloroplasts are able to produce atp molecules to be used by the cell. mitochondria use proteins and nutrients produced in other regions of the eukaryotic cell.

The correct answer is option - 1. Chloroplasts and mitochondria replicate in a similar manner as some prokaryotes.

Explanation:

The endosymbiotic theory says that two eukaryotic cell organelles mitochondria and chloroplast have some prokaryotic especially bacteria-like characteristics and it also said that they are evolved from the symbiotic bacteria, mitochondria from alpha proteobacteria and chloroplast from cyanobacteria.

Thus, the correct answer is option A. Chloroplasts and mitochondria replicate in a similar manner as some prokaryotes.

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