Question

which one of the following remains intact after extensive decomposition and can be used to assist in personal identification of remains? muscle structure bones blood hair

Explanation:

Bones are hard - structured tissues. They have a complex internal and external structure. Muscles are soft tissues that decompose relatively quickly. Blood is a fluid and decomposes easily. Hair, while it can last longer than some soft tissues, does not have the same level of structural integrity and information - rich nature as bones for personal identification after extensive decomposition. Bones can retain features like bone density, bone markings (such as foramina, processes), and in some cases, DNA (although DNA in bones also degrades over time but at a slower rate compared to other tissues in the context of extensive decomposition). These features can be used to match with antemortem (before death) records (such as X - rays, medical records related to bone structure) or through forensic anthropological analysis for personal identification.

Answer:

bones