What are the common symptoms of helminthic infections?

Helminthic infections, caused by parasitic worms, frequently manifest through a range of gastrointestinal and nutritional symptoms, making the correct answer the one that includes abdominal pain, diarrhea, and malnutrition. These symptoms arise from the interaction of the helminths with the host's gastrointestinal system. Helminths can cause inflammation, obstruct the intestines, and compete for nutrients, leading to malnutrition.

Abdominal pain may result from the presence of the worms themselves or from the immune response to the infection. Diarrhea is often a result of the disruption of normal intestinal function and can be a response to the irritation caused by the parasites. Malnutrition is a significant concern, especially in vulnerable populations, as these parasites can cause significant nutrient deficiencies due to their feeding habits.

The other options describe symptoms more commonly associated with other types of infections or conditions rather than helminths. For instance, fever and headache can be related to various infections but are not typically primary symptoms of helminthic diseases. Similarly, skin rashes and respiratory distress lean toward allergic reactions or infections from different pathogens. Coughing and joint pain might be seen in other types of infections or diseases but do not specifically align with the symptomatology of helminth infections.