**Question:** Alpha feto protein is decreased in: (Repeat)

A. Pregnancy
B. Malignant tumors
C. Chronic liver disease
D. Pancreatic disorders

**Core Concept:**
Alpha-feto protein (AFP), also known as human chorionic gonadotropin (hCG), is a glycoprotein produced during pregnancy by the conceptus and later by the placenta. It serves as a marker for fetal development and fetal abnormalities. In addition, AFP is produced in various non-neoplastic conditions such as chronic liver disease and certain pancreatic disorders.

**Why the Correct Answer is Right:**
Alpha-fetal protein is primarily decreased during pregnancy due to its high levels in the maternal circulation during the first trimester and its subsequent decrease as fetal growth and development progresses. In contrast, malignant tumors, specifically hepatocellular carcinoma (HCC), can lead to increased AFP levels due to tumor production and secretion.

**Why Each Wrong Option is Incorrect:**
1. **Option A (Pregnancy):** As mentioned before, AFP levels are high during pregnancy and decrease post-partum. Therefore, AFP levels are not expected to be low in pregnancy.
2. **Option B (Malignant tumors):** Although AFP is produced by hepatocellular carcinomas, it is not the only cause of elevated AFP levels. Various other liver diseases and infections can also lead to increased AFP levels.
3. **Option C (Chronic liver disease):** In chronic liver disease, AFP levels can be elevated due to liver cell destruction and regeneration. However, the question specifically states that AFP is decreased, contradicting this option.
4. **Option D (Pancreatic disorders):** Similar to option B, pancreatic disorders can lead to increased AFP levels, making it an unlikely choice for decreased AFP levels.

**Clinical Pearl:**
When interpreting AFP levels in clinical practice, one must consider the context of the patient's history and clinical presentation. A decreased AFP level can be seen in cases of pregnancy, indicating successful fetal development. However, elevated AFP levels should raise suspicion for malignancies like hepatocellular carcinoma, as well as other liver diseases and infections. In cases of chronic liver disease and pancreatic disorders, elevated AFP levels are more common, not decreased.

**Correct Answer:** Not mentioned in the question

In conclusion, the correct answer is not explicitly stated in the question. However, considering the clinical context, the most plausible reason for decreased AFP levels would be successful fetal development during pregnancy. Elevated AFP levels should prompt further evaluation for hepatocellular carcinoma and other liver diseases and infections.