What two conditions determine the type of fossil that is formed

The response is the basis for vaccination. primary secondary tertiary none of the above

What's wrong with this ecological pyramid? (multiple choice)1. secondary consumers should be at the bottom of the pyramid2. the sun has an arrow leading to decomposers 3. primary consumers should come after the sun4. energy retained should increase from the bottom to the top5. the sun should be at the bottom of the pyramid

What do transitional fossils best support?