Answer: Option C. "Cytoplasm"
Step-by-step explanation:
The gel like fluid that fills most of the cells would be cytoplasm also called protoplasm.
Cytoplasm is enclosed by the cell membrane present within the cell, except for cell nucleus. There are three main components of cytoplasm that involves a gel-like substance called cytosol, various cytoplasmic inclusions, and cell's internal sub-structures. The cytoplasm consist of 80% water and have no color.
Thus, the correct answer is C.