Protein deficiency -> leads to various health issues. Kwashiorkor is a disease caused by protein deficiency.
Kwashiorkor is characterized by -> swelling, fatigue, and poor growth. It is most common in children.
Arthritis is a joint disease -> not directly related to protein deficiency. It is an autoimmune disease.
Goitre is caused by iodine deficiency -> not protein deficiency. It leads to thyroid problems.
Night blindness is caused by vitamin A deficiency -> not protein deficiency. It affects vision in low light.
Correct answer: Option 2 -> Kwashiorkor.