The genome of modern chloroplasts is roughly 50% the size of the genome of the cyanobacterium from which it is thought to have been derived. In comparison, the genome of P. chromatophora is chromatophore is only slightly reduced relative to the size of the genome of the cyanobacterium from which it is thought to have been derived. What is a valid hypothesis that can be drawn from this comparison

The endosymbiotic incorporation of a cyanobacterium into a eukaryotic host cell offered to ascend to the basic progenitor of the Archaeplastida that along these lines split into the three essential plastid genealogies, Glaucophyta, Viridiplantae, and Rhodophyta
Endosymbionts and their hosts frequently speak to the distinct domains of life. As an outcome, their amalgamation can create totally new blends of biochemical capacities and permit the two, interweaved species to flourish in conditions that would be aloof to either alone
The examination of the total chromatographic genome sequence of P. chromatophore strain CCAC 0185 uncovered a principal genome decrease. The single, round chromosome of 1.02 Mb encodes just 867 protein-coding genes and is, therewith, the littlest cyanobacterial genome reported to date
In spite of the fact that the chromatophore genome contains a practically complete arrangement of photosynthesis genes, it needs not just genes thought to be nonessential for an intracellular way of life yet additionally genes of fundamental pathways for amino corrosive and cofactor biosynthesis
Hence, the right answer is "P. Chromatophore is a result of evolutionarily recent endosymbiosis"