**Core Concept**
The patient's presentation suggests a high likelihood of a renal injury, specifically a renal laceration or avulsion, given the mechanism of injury and the absence of left kidney excretion on the intravenous pyelogram (IVP). Renal injuries are classified based on the American Association for the Surgery of Trauma (AAST) Organ Injury Scale.

**Why the Correct Answer is Right**
The correct answer involves obtaining a CT scan of the abdomen and pelvis to further evaluate the extent of the renal injury and potential complications such as hemorrhage, ureteral injury, or collecting system disruption. The CT scan will provide detailed information about the location, severity, and potential complications of the renal injury, guiding further management. The presence of hematuria and flank pain, along with the mechanism of injury, necessitates a thorough evaluation of the renal injury.

**Why Each Wrong Option is Incorrect**
**Option A:** Immediate surgical exploration is not typically the next step in management, as it is often reserved for patients with hemodynamic instability or severe renal injury. A CT scan would provide more information before proceeding to surgery.

**Option B:** Bed rest and observation are not appropriate for a patient with a suspected renal injury, as the injury may worsen over time, leading to complications such as hemorrhage or ureteral obstruction.

**Option C:** Angiography may be considered for patients with evidence of active bleeding, but it is not the next step in management for a patient with a suspected renal injury who has not shown signs of hemodynamic instability.

**Option D:** Urology consultation is important, but it is not the next step in management. The primary step is to obtain a CT scan to evaluate the extent of the renal injury.

**Clinical Pearl / High-Yield Fact**
The presence of hematuria and flank pain in a patient with a history of trauma should raise suspicion for a renal injury. A CT scan of the abdomen and pelvis is essential in the evaluation of renal injuries to guide management and prevent complications.

**Correct Answer:** C.