**Core Concept**
Suppurative labyrinthitis is an infection of the inner ear that can cause hearing loss, vertigo, and tinnitus. The Rinne test assesses the patient's ability to hear a tuning fork in air versus bone conduction, and is used to differentiate between conductive and sensorineural hearing loss.

**Why the Correct Answer is Right**
In the initial examination, the patient had a positive Rinne's test, indicating that air conduction was better than bone conduction. However, after 2 weeks of untreated suppurative labyrinthitis, the patient's condition likely worsened, leading to a sensorineural hearing loss. As a result, the patient's bone conduction would be impaired, and the Rinne test would become **negative**, indicating that bone conduction is better than air conduction.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because a positive Rinne's test would not be expected in a patient with sensorineural hearing loss, which is likely in this case.
**Option B:** This option is incorrect because the patient's condition worsened over time, making it unlikely that the Rinne test would remain positive.
**Option C:** This option is incorrect because the patient's bone conduction would be impaired due to sensorineural hearing loss, making it unlikely that the Rinne test would become positive.

**Clinical Pearl / High-Yield Fact**
Remember that the Rinne test can become negative in cases of sensorineural hearing loss, and that a negative fistula test does not rule out the possibility of a perilymphatic fistula.

**Correct Answer:** B. The Rinne test would become negative.