Cyanobacteria also known as one of the first organism on earth are responsible for producing nearly 80% of the oxygen on earth.
Only the last one provides an actual evidence of having a common ancestor. The rest can be a result of living in a similar environments that makes life easier. For example, many species live next to water, as water provides more fertile ground for plants, and they might have similar behaviors (searching for water) but they might not be closely related.
so the correct answer is D.
A. they arose out of Africa less than 200,00 years ago
Remember the definition of Osmosis; Water travels through a semipermeable membrane to an area of higher to lower concentration. Since the concentration of a solute is higher outside, we can make the assumption that water concentration is lower, and so the cell is going to release water to balance out and equalize the solution and it's surroundings.
