**Core Concept**
Congenital anorectal malformations (ARM) are a group of complex congenital anomalies characterized by abnormal development of the anorectal region. These anomalies can vary in severity and involve the rectal, anal, and genital structures. The diagnosis of ARM often relies on a combination of clinical evaluation, imaging studies, and surgical exploration.

**Why the Correct Answer is Right**
Radiographic imaging, particularly X-ray, can be useful in detecting ARM by visualizing the abnormal position and course of the rectal and anal structures. In particular, a barium enema X-ray can help identify the presence of a rectal pouch or a fistula connecting the rectum to the urinary tract. This information is crucial for planning surgical intervention and guiding the surgeon during the procedure. The X-ray can also help differentiate between different types of ARM, such as high and low anomalies.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while ultrasound is a valuable tool in the evaluation of ARM, it is not the primary modality for detecting these anomalies.
**Option B:** This option is incorrect because while MRI can provide detailed images of the anorectal region, it is not typically used for initial diagnosis of ARM.
**Option C:** This option is incorrect because while CT scans can be used to evaluate the extent of ARM, they are not the best modality for initial detection.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the diagnosis of ARM often requires a multidisciplinary approach, involving pediatric surgeons, radiologists, and other specialists. The use of a barium enema X-ray can help identify the presence of a rectal pouch or fistula, which is crucial for planning surgical intervention.

**Correct Answer: C. CT scans**