**Core Concept**
Biliary atresia is a congenital condition characterized by the obstruction of the bile ducts, leading to liver damage and cirrhosis if left untreated. In infants undergoing surgery for biliary atresia, the anaesthetic plan must consider the potential for hypoxia, acidosis, and the need for precise control of body temperature.

**Why the Correct Answer is Right**
In a 2-month-old infant undergoing surgery for biliary atresia, it is crucial to avoid anaesthetics that can cause histamine release, leading to hypotension and potential cardiovascular instability. This is particularly relevant for anaesthetics that can cause histamine release, such as **tracheal intubation with succinylcholine**. Succinylcholine can cause a significant release of histamine, leading to hypotension, tachycardia, and bronchospasm, which can be catastrophic in a patient with compromised liver function.

**Why Each Wrong Option is Incorrect**
**Option A:** Propofol is a commonly used anaesthetic agent in infants and is not typically contraindicated in biliary atresia.

**Option B:** Fentanyl is a synthetic opioid that can be used in infants and does not have a significant effect on histamine release.

**Option C:** Desflurane is a volatile anaesthetic agent that can cause airway irritation, but it is not typically contraindicated in biliary atresia.

**Clinical Pearl / High-Yield Fact**
In infants undergoing surgery for biliary atresia, it is essential to maintain precise control of body temperature, as hypothermia can exacerbate liver dysfunction and increase the risk of complications.

**Correct Answer: A. Succinylcholine. It is generally avoided in infants undergoing surgery for biliary atresia due to the potential for histamine release and subsequent cardiovascular instability.**