Which of the following statements support(s) the theory of the endosymbiotic origin of mitochondria and plastids? I Mitochondria and plastids have circular DNA and replicate by splitting.
II Mitochondria and plastids have ribosomes.
III Mitochondrial and plastid ribosomal RNA sequences are more similar to cytoplasmic ribosomes than to bacterial ones.
IV The inner membranes of plastids and mitochondria have transport proteins homologous to those in bacterial plasma membranes.

I only
I and II only
III only
I, II, and IV