Answer: W.M. Stanley.
- A D.J. Ivanowsky
- B M.W. Beijerinck
- C W.M. Stanley
- D Louis Pasteur
Correct answer: C. W.M. Stanley
Explanation: W.M. Stanley (1935) showed that viruses could be crystallized, and crystals consist largely of proteins. D.J. Ivanowsky first reported viruses, and Beijerinck described the contagious nature of the virus.
Whittaker's five-kingdom system (1969) groups all cellular life by cell structure and nutrition; viruses, viroids, and lichens fall outside this system entirely since they aren't independently classifiable as one of the five.
Concept context
Whittaker's five kingdom system covering Monera, Protista, Fungi, plus viruses, viroids, and lichens. A foundational NEET chapter on how living organisms are grouped.