Fossils can be found in the Earth's crust.
The crust is the thinnest layer of the Earth. The fossils are most probably be found in this layer because it is the outermost layer. Also, the deeper the layer of the Earth, the higher the temperature that it has, and it probably cannot preserve the fossil.
The correct answer is option A. Carrying the genetic code and determining an organism's structure and function are the functions of DNA. It is the hereditary material in almost all other organisms. The information in a DNA is stored as codes that is composed of chemical bases.
I think Leonardo could have a point but I’m pretty sure it’s just based on genetics even with sea monsters lol