**Core Concept**
Morphine withdrawal occurs when an individual who has developed physical dependence on morphine suddenly stops taking the drug or experiences a significant decrease in dosage. This leads to a complex array of symptoms due to the body's adaptive changes during prolonged morphine exposure, including changes in neurotransmitter levels and receptor sensitivity.

**Why the Correct Answer is Right**
During morphine withdrawal, individuals typically experience symptoms such as anxiety, insomnia, sweating, muscle aches, and nausea. These symptoms arise due to the sudden decrease in endorphin and enkephalin levels in the brain, which were initially increased by chronic morphine exposure. The body attempts to compensate for the loss of opioid receptors by increasing the release of these natural opioids, leading to the characteristic symptoms of withdrawal.

**Why Each Wrong Option is Incorrect**
**Option A:**
* This option is not a typical symptom of morphine withdrawal. Morphine withdrawal primarily affects the central nervous system and does not usually cause peripheral neuropathy.

**Option B:**
* This option is incorrect because yawning is actually a common symptom of opioid withdrawal, including morphine. Yawning is thought to be a manifestation of the body's attempt to increase the release of endorphins and other natural opioids.

**Option C:**
* This option is not a characteristic symptom of morphine withdrawal. While anxiety and insomnia are common symptoms, restlessness is not a specific or distinctive symptom of morphine withdrawal.

**Clinical Pearl / High-Yield Fact**
The timing and severity of morphine withdrawal symptoms can be managed with the use of opioid receptor antagonists such as naloxone and naltrexone. These medications can help alleviate withdrawal symptoms by blocking opioid receptors and reducing the body's craving for opioids.

**Correct Answer: D. Peripheral neuropathy.**