Answer:
C. active transport.
Step-by-step explanation:
Pinocytosis is a cellular process in which "ingestion" occurs, that is, the incorporation of fluids by a cell. These fluids are rich in dissolved substances and as this process refers to the cell's ability to "swallow" something, we can say that it is a type of endocytosis.
This process occurs with cellular energy expenditure, for this reason, we can say that pinocytosis is an example of active transport.