Answer:
Option B is likely originated from photosynthetic bacteria.
Explanation:
A) pellicle and contractile vacoule
B) Stigma and chloroplast (photosynthetic bacteria)
C) reservoir and flagellum
D) photoreceptor and Nucleolus
Euglena is a genus of single cell flagellate eukaryotes. Euglena have features of both animals and plants. Euglena have photosynthesizing chloroplasts within the body of the cell, which enable them to feed by autotrophy, like plants. Euglena's chloroplasts evolved from a eukaryotic green alga. Thus, the intriguing similarities between Euglena and the plants have arisen of a secondary endosymbiosis. Molecular phylogenetic analysis support this hypothesis but this is not generally accepted. A stigma (red eyespot) is located near the base of the reservoir and this filters the light and focuses it on the paraflagellar body, and is involved in the phototaxis of this alga.
