What type of fossil involves the original organism being preserved in its entirety?

A body fossil represents the original organism being preserved in its entirety, which includes structures such as bones, teeth, or even soft tissues in some rare cases like amber-preserved insects or frozen mammoths. This type of fossil provides valuable information about the anatomy, structure, and sometimes even the behavior of the organism, as it reflects its physical form at the time of its preservation.

In contrast, mould fossils capture the external shape of an organism but do not contain any organic material, while cast fossils are formed when a mould is filled with sediment or minerals, replicating the shape but not preserving the organism itself. Trace fossils, on the other hand, consist of indirect evidence of an organism's activities, such as footprints, burrows, or feces, rather than the organism's physical form. Thus, body fossils are distinct in their ability to preserve the actual remains of the organisms, making them crucial for understanding the history of life on Earth.