Are insects a fool-proof way to determine time of death? why or why not?

Insects are usually the first to arrive at a death scene. Determining time since death is of paramount importance in a death investigation. Knowing time since death directs the police investigation into the correct time frame. Additionally, this type of information can help support or refute a suspect’s alibi, help in the identification of an unknown victim, and improve efficacy of the police investigation.

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The answer is d because , safety almost always works, to prevent stds and pregnancy