Which experiments led to changes to the original cell theory?

Question: Which experiments led to changes to the original cell theory? 

(1)experiments that showed that blood cells transport gases, waste, and nutrients throughout the body.

(2)experiments that showed that all cells are similar in how they metabolize and in their composition.

(3)the experiments that established the existence of single-celled organisms and microbes.

(4)the experiments that transplanted synthetic chromosomes into bacterial cells to create a new species.

Answer (3) is absolutely right answer because we know that the experiments that established the existence of single-celled organisms and microbes.