Which of the following would NOT be considered evidence of past earth events that could help us determine when those events happened? A.
layers of rock that show a volcanic eruption wiped out most life 250 million years ago

B.
finding a shell fossil in limestone

C.
find a trilobite fossil in a 250 million-year-old rock below a 165 million-year-old dinosaur fossil

D.
determining mammals appeared on earth 240 million years ago

The answer is option D "determining mammals appeared on earth 240 million years ago"

Explanation:

Regardless of appearing to be a generally steady spot, the World's surface has changed significantly over the past 4.6 billion years. Mountains have been constructed and dissolved, mainlands and seas have moved significant stretches, and the Earth has varied from being incredibly cold and totally covered with ice to being warm and without ice. These progressions commonly happen so gradually that they are scarcely distinguishable over the range of a human existence, yet even at right now, the World's surface is moving and evolving. As these progressions have happened, creatures have advanced, and remainders of some have been safeguarded as fossils.

hola:

ef0: daños leves. algunas tejas caídas y otras pequeñas piezas de los tejados arrancadas, algunos daños en canaletas, ramas de árboles rotas y algunos árboles poco profundos arrancados. los tornados que no causan daños visibles (por ejemplo aquellos que se producen en campos abiertos) se valoran siempre como de ef0.

ef1: daños moderados. tejados seriamente despedazados, caravanas y casetas volcadas o seriamente dañadas, perdida de puertas exteriores y ventanas y otros cristales rotos.

ef5: daños increíbles. las casas fuertes pueden quedar arrasadas hasta los cimientos, las estructuras de hormigón armado dañadas críticamente, los edificios altos sufren graves deformaciones estructurales. devastaciones increíbles.

y según esto creo que puedes sacar tus conclusiones. y la verdad la escala ef10 si no se decirte por que no la eh visto o mejor dicho estudiado. espero que te sirva. suerte.