**Core Concept**
Ghotna is a form of torture or punishment used historically, where a heavy object, typically a wooden log, is rolled on the victim's leg to cause severe pain and potentially lead to amputation or other complications. This method of torture is considered a form of physical abuse and is often associated with medieval times.

**Why the Correct Answer is Right**
The correct answer, **Option A: Heavy wooden log rolled on leg**, is the correct definition of Ghotna. This method of torture involves the use of a heavy object, such as a wooden log, to inflict severe pain on the victim. The log is typically rolled on the victim's leg, causing crushing injuries and potentially leading to amputation. The use of a heavy object in this manner is a classic example of a form of torture that was used in the past to inflict pain and suffering on victims.

**Why Each Wrong Option is Incorrect**

* **Option B:** Compressing the thighs with two roads - This option is incorrect because Ghotna does not involve compressing the thighs with two roads. While compression injuries to the thighs can be serious, this is not the definition of Ghotna.
* **Option C:** Tying the limbs to the pole - This option is incorrect because Ghotna does not involve tying the limbs to a pole. While this can be a form of restraint, it is not the definition of Ghotna.
* **Option D:** Electric shock to genitalia - This option is incorrect because Ghotna does not involve electric shock to the genitalia. Electric shock is a different form of torture that can cause severe pain and damage to the genitalia.

**Clinical Pearl / High-Yield Fact**
It is essential for forensic medicine students to be aware of various forms of torture and punishment used historically, as they can provide valuable insights into the development of forensic science and the importance of protecting human rights.

**✓ Correct Answer: A. Heavy wooden log rolled on leg**