Which statement about all living organisms is true? A) They have limbs.

B) They breathe air.

C) They have at least one cell.

Pluto was once classified as a planet. however, scientists no longer classify pluto as a planet. which is a likely reason for this change? the original hypothesis about pluto was supported. no observations of pluto were made in the past. several planets in outer space were found to be similar to pluto. there were significant changes in scientific knowledge about planets.