- The cell theory was postulated by Theodor Schwann and Matthias Schleiden in 1838. They are as follows-
- All living organisms are composed of one or more cells.
- The cell is the most basic unit of life.
- The third was added by Rudolf Virchow in 1855, which stated: "Omnis cellula e cellula" which means all cells arise only from pre-existing cells.
So, the correct answer is option B.