Question

Which is not a factor in a fossil organism being useful as an index fossil? It must have lived through a long span of time. It must be widespread geographically. It must be abundant. It must be limited to a short span of geologic time.

Answer 1

it must have lived through a long span of time

Answer 2

Answer:Option (1)

Explanation: Index fossil are those fossils that appears for a very short period of time in the geological time scale and has a wide geographical distribution. For example, Ammonites.

Index fossils are a good source for rock age determination and also it helps in the correlation of rocks.

Thus, the correct answer is option (1).