The fluid content inside the plasma membrane is named:

The correct option is Cytoplasm.

Explanation:
The cytoplasm is the jelly-like fluid content that is enclosed by the plasma membrane of a cell. It serves as the medium for chemical reactions and houses the cell's organelles, facilitating various cellular processes. It consists mainly of water, salts, and organic molecules.

Here is a breakdown of why the other options are incorrect:
• Chromatin: This is a substance within a cell nucleus consisting of DNA and proteins, which condenses to form chromosomes during cell division.
• Genes: These are specific segments of DNA that contain instructions for making proteins, acting as the basic units of heredity.
• Chromosomes: These are thread-like structures composed of DNA and proteins located inside the nucleus that carry genetic information.

Since chromatin, genes, and chromosomes are genetic components located within the nucleus, the only fluid content filling the space inside the plasma membrane is the cytoplasm.