**Core Concept**
Congenital rubella syndrome (CRS) is a condition that occurs in infants born to mothers who have been infected with the rubella virus during pregnancy. It is characterized by a range of congenital abnormalities due to the teratogenic effects of the virus.

**Why the Correct Answer is Right**
Renal anomalies are not typically associated with congenital rubella syndrome. The rubella virus is known to cause damage to the developing fetus, leading to a range of congenital abnormalities, including cardiac, ophthalmic, auditory, and neurological problems. However, renal anomalies are not commonly reported in cases of CRS. In contrast, cardiac abnormalities, deafness, and cataracts are well-documented consequences of CRS.

**Why Each Wrong Option is Incorrect**
**Option A:** Cardiac abnormality – This is a true statement about CRS. The rubella virus is known to cause cardiac abnormalities, including patent ductus arteriosus, pulmonary artery stenosis, and atrial septal defects.
**Option C:** Deafness – This is also a true statement about CRS. The virus can cause congenital deafness or hearing loss in affected infants.
**Option D:** Cataract – This is another true statement about CRS. Congenital cataracts are a common feature of CRS, resulting from the teratogenic effects of the virus on the developing lens of the eye.

**Clinical Pearl / High-Yield Fact**
Remember that CRS is a preventable condition through vaccination. The rubella vaccine is a crucial component of immunization programs worldwide, and vaccination of pregnant women is recommended to prevent maternal rubella and subsequent CRS.

**✓ Correct Answer: B. Renal anomalies**