Study the different conclusions drawn by students of a class on the basis of observations of preserved / available specimens of plants and animals. I. Potato and sweet potato are analogous organs in plants. II. Wings of insects and wings of birds are homologous organs in animals. III. Wings of insects and wings of bats are analogous organs in animals. IV. Thorns of citrus and tendrils of cucurbita are analogous organs in plants. The correct conclusions are:

Let us analyze each statement to determine its correctness:

1. Statement I (Potato and sweet potato are analogous organs in plants): This is correct. A potato is a modified underground stem (tuber) while a sweet potato is a modified adventitious root. They have completely different structural origins but perform the same function of food storage. Therefore, they are analogous organs.
2. Statement II (Wings of insects and wings of birds are homologous organs in animals): This is incorrect. The wings of insects (composed of thin chitinous membranes) and the wings of birds (composed of bony forelimbs covered with feathers) have different structural designs and origins but perform the same function of flight. Therefore, they are analogous, not homologous.
3. Statement III (Wings of insects and wings of bats are analogous organs in animals): This is correct. The wings of insects and bats have different basic anatomical structures and origins but serve the same function (flight).
4. Statement IV (Thorns of citrus and tendrils of cucurbita are analogous organs in plants): This is incorrect. Both the thorns of citrus and the tendrils of cucurbita arise from the axillary bud position, meaning they share a common structural origin. Thus, they are homologous organs, even though they perform different functions (protection and climbing, respectively).

Since statements I and III are correct, the correct option is C.