When the cell engulfs small, dissolved particles, it is called a)endocytosis b)exocytosis c)pinocytosis d)phagocytosis

Option C, Pinocytosis

Explanation:

Pinocytosis is the process through which a particle suspended/dissolved in a liquid is ingested into a cell while endocytosis is a process through which a cell ingests all food and liquid particles.  

There are three types of endocytosis - phagocytosis, pinocytosis, and receptor-mediated endocytosis.

Thus, pinocytosis is a more defined terminology for ingestion of dissolved food while endocytosis is ingestion of all sorts of food.  

In both pinocytosis and endocytosis a cell approaches a particle of matter and extends its membrane to form vesicles to encircle the food/liquid particle . The earliest form of life on planet earth such as amoeba used to ingest food in this way.  

Thus the most suitable terminology for  the ingestion of dissolved particle is pinocytosis

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