**Core Concept**
Ophthalmologic evaluation in children with type I diabetes mellitus (DM) is crucial to detect and prevent diabetic retinopathy, a common complication of diabetes. Diabetic retinopathy is characterized by damage to the blood vessels in the retina, leading to vision loss if left undiagnosed and untreated.

**Why the Correct Answer is Right**
The American Academy of Pediatrics recommends ophthalmologic evaluation in children with type I DM starting at 10 years of age or 5 years after the onset of diabetes, whichever comes first. This is because the risk of developing diabetic retinopathy increases with the duration of diabetes. Regular ophthalmologic evaluation allows for early detection and treatment of retinopathy, preventing vision loss and improving outcomes.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because ophthalmologic evaluation is not indicated in children with type I DM at the time of diagnosis. While initial evaluation is crucial, it is not until 5 years after the onset of diabetes that the risk of developing retinopathy increases.

**Option B:** This option is incorrect because ophthalmologic evaluation is not solely indicated in children with type I DM who have had diabetes for 10 years. While duration of diabetes is a risk factor, other factors such as blood pressure and lipid levels also play a role.

**Option C:** This option is incorrect because ophthalmologic evaluation is not indicated in children with type I DM who have no symptoms. Diabetic retinopathy can be asymptomatic in its early stages, making regular ophthalmologic evaluation essential for early detection.

**Clinical Pearl / High-Yield Fact**
Regular ophthalmologic evaluation in children with type I DM is crucial to prevent vision loss due to diabetic retinopathy. The American Academy of Pediatrics recommends starting ophthalmologic evaluation at 10 years of age or 5 years after the onset of diabetes, whichever comes first.

**Correct Answer:** C.