Which of the following experiments would support the belief that lack of protein causes pellegra

1 giving fruits that contain vitamin c to animals with pellegra
2 reducing the intake of high quality proteins and healthy animals and monitoring the results
3 inoculating healthy individuals with secretions from pellegra skin lesions
4 nothing healthy animals live in on sanitary
5 moving animals with pellegra llegra into sanitary environment

2 reducing the intake of high-quality proteins in healthy animals and monitoring the results.