What is a primary symptom of scurvy?

One of the primary symptoms of scurvy is weakness and bleeding of the gums. Scurvy is caused by a deficiency of vitamin C, which is essential for collagen synthesis in the body. Collagen is a crucial protein that helps maintain the structure of blood vessels, skin, and connective tissues. When there is insufficient vitamin C, the body cannot produce collagen effectively, leading to weakened blood vessels and gum tissue. This results in symptoms such as swollen and bleeding gums, along with general weakness.

Understanding the relationship between vitamin C and collagen formation highlights why bleeding gums is a hallmark symptom of scurvy. In contrast, excessive thirst, swelling of joints, and frequent headaches are not direct indicators of scurvy and can be attributed to various other health issues or deficiencies. Thus, weakness and bleeding of gums distinctively point to the underlying cause of scurvy, making it the correct answer.