**Core Concept**
Incineration is a widely accepted method for disposing of human anatomical waste, including placentas, in primary health care settings. This practice ensures the complete destruction of the waste, minimizing the risk of pathogen transmission and environmental contamination.

**Why the Correct Answer is Right**
Incineration involves the high-temperature combustion of organic materials, resulting in the complete destruction of the waste. This process is particularly effective in eliminating pathogens and reducing the volume of waste. In the context of placental disposal, incineration is considered a safe and efficient method, as it eliminates the risk of disease transmission and reduces the need for specialized storage facilities. The World Health Organization (WHO) and other reputable health organizations recommend incineration as the preferred method for disposing of human anatomical waste.

**Why Each Wrong Option is Incorrect**
**Option B:** Microwaving is not a recommended method for disposing of placentas, as it may not achieve the high temperatures necessary for pathogen destruction and can create hazardous fumes.

**Option C:** Autoclaving, while effective for sterilizing equipment and certain medical waste, is not suitable for disposing of placentas due to the risk of incomplete pathogen destruction and potential for re-contamination.

**Option D:** Chemical treatment is not a recommended method for disposing of placentas, as it may not be effective in eliminating all pathogens and can create hazardous chemical residues.

**Clinical Pearl / High-Yield Fact**
It is essential to follow local and national guidelines for the disposal of human anatomical waste, including placentas, to ensure the safety of healthcare workers, patients, and the environment. Incineration is a widely accepted method, but other methods may be recommended in specific circumstances.

**✓ Correct Answer: A. Incineration**