Step 1: Know what ringworm is.
Ringworm is not caused by a worm. It is a fungal infection of the skin that makes ring-shaped patches.
Step 2: Check statement I about the cause.
Ringworm is caused by a group of fungi. Epidermophyton is one of the genera that cause it, along with Trichophyton and Microsporum. So statement I is correct.
Step 3: Think about where the fungus likes to grow.
These fungi grow best in places that are warm and damp, where sweat collects and air does not reach well.
Step 4: Check statement II about body sites.
Skin folds such as the groin and the gaps between the toes stay moist and warm. Ringworm often appears in these spots. So statement II is correct.
Step 5: Combine the two statements.
Both statement I and statement II are correct.
Step 6: Pick the option.
The choice that says both statements are correct is the first one.
\[ \boxed{\text{Statement I and II are correct}} \]