**Core Concept**
Injury to any private part of the body of a woman with the intent to outrage her modesty comes under Sec 320 IPC.

**Why the Correct Answer is Right**
Sec 320 IPC specifically includes injuries to private parts of a woman with the intent to outrage her modesty. This includes intentional acts that may cause physical harm or damage to a woman's private body parts, with the intent of causing her to lose her sense of dignity or modesty. This section is designed to protect women from such acts of violence and harassment.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because Sec 320 IPC specifically mentions injuries to private parts of a woman with the intent to outrage her modesty, not any injury to a woman's body.
* **Option B:** This option is incorrect because Sec 320 IPC is not limited to grievous hurt, but specifically includes injuries to private parts of a woman with the intent to outrage her modesty.
* **Option C:** This option is incorrect because Sec 320 IPC does not include all types of injuries to a woman's body, but specifically mentions injuries to private parts with the intent to outrage her modesty.
* **Option D:** This option is incorrect because Sec 320 IPC is not limited to voluntarily causing hurt, but specifically includes injuries to private parts of a woman with the intent to outrage her modesty.

**Clinical Pearl / High-Yield Fact**
Remember that Sec 320 IPC specifically includes injuries to private parts of a woman with the intent to outrage her modesty, making this a high-yield topic for medical professionals and law enforcement officials.

**Correct Answer: D. Voluntarily causing grievous hurt.**