Rigor mortis occurs as early as how many minutes after death?

Rigor mortis typically begins to set in within approximately 10 to 15 minutes after death. The process is initiated by the biochemical changes occurring in the muscles as the body starts to break down without the circulation of blood, which delivers oxygen and removes waste products.

In this timeframe, the body experiences muscle stiffening due to the depletion of ATP (adenosine triphosphate), which is essential for muscle relaxation. This stiffening can be observed in both small and large muscle groups, spreading gradually throughout the body.

The other options suggest earlier times (5 minutes) or slightly later than the typical onset (15 or 20 minutes), which do not align with the widely accepted biological processes involved in rigor mortis. Hence, the timeframe of around 10 minutes directly correlates with these physiological changes postmortem, making it the most accurate choice.