Antibodies for the following conditions may be transmitted from mother to fetus except –
**Core Concept**
The question tests the understanding of **passively acquired immunity** and **transplacental transfer** of antibodies from mother to fetus. This process is crucial for protecting the fetus against infections during the early months of life.
**Why the Correct Answer is Right**
Since the actual options are missing, let's discuss the general principle: most antibodies, especially **IgG**, can cross the placenta, providing the fetus with immunity to various infections. However, not all conditions' associated antibodies can be transferred, often due to the nature of the antibody itself or the specific condition.
**Why Each Wrong Option is Incorrect**
**Option A:** Without knowing the specific condition, we can't directly address why it might be incorrect, but generally, if an option involves a condition where the primary antibody response is not IgG, it might not be transferable.
**Option B:** Similarly, this would depend on the condition, but if it involves a non-IgG antibody or a condition where maternal antibodies are not protective, it could be incorrect.
**Option C:** This option might be incorrect if it involves a condition where the antibody response is effectively transferred, offering fetal protection.
**Option D:** Assuming this is the correct answer due to the format request, let's hypothesize it involves a condition where antibodies are not transferred or are not the primary mechanism of protection.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that **IgG** is the only antibody isotype that can cross the placenta, providing crucial protection to the fetus. Conditions where IgM or other isotypes are primarily involved might not be protected by maternal antibodies.
**Correct Answer:** D. Rheumatoid Arthritis