1. when might preserved remains of an entire organism form? a. when sediment buries the hard part of an organism. b. when an event such as a quick burial or freezing preserves an entire organism. c. when minerals replace parts of an organism. d. when a thin layer of carbon is left on a rock 2. which of the following fossil types is formed when minerals replace all or part of an organism's body? a. a mold. b. a petrified fossil. c. a cast. d. a trace fossil