Match column-I (scientists) with column-II (discovery) and select the correct option. Column-I Column-II A. Leeuwenhoek I. First saw and described a living cell. B. Robert Brown II. Presence of cell wall is unique to plant cells. C. Schleiden III. Discovered the nucleus. D. Schwann IV. All plants are composed of different kind of cells.

• A. A-I; B-III; C-IV; D-II
• B. A-I; B-III; C-II; D-IV
• C. A-III; B-I; C-IV; D-II
• D. A-I; B-IV; C-II; D-III