On microscopic examination, eggs are seen, but on saturation with a salt solution, no eggs are seen. The eggs are likely to be of –
**Core Concept**
Taenia solium eggs, also known as pork tapeworm eggs, are an example of eggs that are embryonated and have a thick, outer layer. This characteristic makes them resistant to salt solutions, unlike other types of eggs.
**Why the Correct Answer is Right**
The correct answer is B. Taenia solium because its eggs have a unique, thick outer layer that prevents them from dissolving or dehydrating when exposed to a salt solution. This is due to the presence of a glycoprotein layer on the eggshell, which protects the embryo inside. When a salt solution is applied, it cannot penetrate the eggshell and cause the egg to dissolve, unlike other types of eggs. This characteristic is a key diagnostic feature of Taenia solium eggs.
**Why Each Wrong Option is Incorrect**
**Option A:** Trichuris trichiura eggs, or whipworm eggs, are not resistant to salt solutions and would typically dissolve or dehydrate when exposed to such a solution.
**Option C:** Ascaris lumbricoides eggs, or roundworm eggs, are not resistant to salt solutions and would also typically dissolve or dehydrate when exposed to such a solution.
**Option D:** Ancylostoma duodenale eggs, or hookworm eggs, are not resistant to salt solutions and would typically dissolve or dehydrate when exposed to such a solution.
**Clinical Pearl / High-Yield Fact**
One key point to remember is that the resistance of Taenia solium eggs to salt solutions is a critical diagnostic feature that can help differentiate them from other types of eggs, particularly those of other parasitic worms.
**✓ Correct Answer: B. Taenia solium**