What is cytoplasm primarily composed of?

Cytoplasm is primarily composed of the cell's liquid matrix, which is also known as cytosol. This semi-fluid component surrounds the organelles within the cell and serves as the medium in which various biochemical reactions occur. The composition of cytosol includes water, salts, organic molecules, and a variety of substances that facilitate essential cellular processes.

The other options do not accurately represent the nature of cytoplasm. While membranes and organelles exist within the cytoplasm, they do not constitute the primary component of it. Cytoplasm includes both the liquid (cytosol) and the structures suspended in it, making it a complex mixture rather than consisting of solids or only organelles. Therefore, the best answer to the question reflects the predominant component of cytoplasm — its liquid matrix.