Euglena are protists that move by means of flagella, and they contain chloroplasts and an eye spot or light receptor. They are capable of ingesting food by phagocytosis. Being simple organisms, they can reproduce asexually.

Under what environmental condition would we expect euglena to ingest food rather than produce food via photosynthesis?

A) when light is limited
B) when light is abundant
Eliminate
C) when oxygen is limited
D) when temperatures drop