According to the theory of endosymbiosis, early eukaryotes evolved by symbiotic association of prokaryotes. witch two protists evolved from a symbiotic relationship of organisms. which resulted in eukaryotic organisms containing chloroplasts

Examples of protists that possibly evolving form endosymbiosis are Paramecium and amoeba. 

As per the theory of endosymbiosis, it is likely that some non-photosynthetic organisms formed a symbiotic relationship with organisms that had the ability to photosynthesize using chloroplasts. These organisms then got the ability to photosynthesize due to the addition of chloroplasts into their cells, and this resulted in eukaryotic organisms with chloroplasts.

Except hold on to his or her beliefs even if there is no evidence for those beliefs.

Iwould say silver and gold