**Core Concept**
Sterile haemorrhagic cystitis is a condition characterized by bleeding from the bladder mucosa in the absence of an infectious cause. This condition often occurs as a side effect of certain medications.

**Why the Correct Answer is Right**
The correct answer is Cyclophosphamide, a chemotherapeutic agent that is metabolized to acrolein, a toxic compound that causes damage to the bladder mucosa, leading to hemorrhage. Cyclophosphamide is commonly used in the treatment of various cancers, and its use is associated with an increased risk of sterile hemorrhagic cystitis. The mechanism of action involves the formation of acrolein, which covalently binds to DNA, causing damage to the bladder epithelium.

**Why Each Wrong Option is Incorrect**
**Option A:** Ifosfamide is another chemotherapeutic agent that can cause hemorrhagic cystitis, but it is not the most common cause. It is also metabolized to acrolein, but its use is less frequently associated with this side effect.
**Option B:** Mitomycin C is an antineoplastic agent that can cause hemorrhagic cystitis, but it is not as strongly associated with this side effect as cyclophosphamide.
**Option C:** Cisplatin is a chemotherapeutic agent that can cause various side effects, but it is not commonly associated with hemorrhagic cystitis.

**Clinical Pearl / High-Yield Fact**
It is essential to monitor patients receiving cyclophosphamide for signs of hemorrhagic cystitis, such as hematuria, and to consider the use of protective agents like mesna to reduce the risk of this side effect.

**Correct Answer: C. Cyclophosphamide**