The physical basis of life is: (NSCL 2018)

✅Explanation: Protoplasm is the living substance within a cell, encompassing both the cytoplasm and the nucleus. It's considered the physical basis of life as it's where all the vital cellular processes occur.

📌Other Options Explanations:
-Cytoplasm: The jelly-like substance within a cell excluding the nucleus.
-Nucleoplasm: The substance within the nucleus.
-Endoplasm: The inner, denser part of the cytoplasm in some cells

🔑Key Points:
Protoplasm is the colourless material comprising the living part of a cell, including the cytoplasm, nucleus, and other organelles. It is known and considered as the physical basis of life.