Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Saurabh 1
Graptolites appeared during late cambrian or one can say in cambrian around 500mya and they rose to dominance in and around ordovician and silurian. They got extinct in carboniferous. Trilobite got extinct in end permian major mass extinction (i would say the most catastrophic extinction event ) around 250mya. So correct option has to be (B).
sir...bt mene toh ab tk yahi padha hai... Devonian me extinct ho gye the graptolites
Nahi bhai go through some legit sites like british geological survey there you will see that they finally ended in carboniferous not completely in devonian so most probably the answer would be carboniferous
https://www.bgs.ac.uk/discovering-geology/fossils-and-geological-time/graptolites/
Dear gurmeet go through this you will get to know what I was saying.. Actually there are alot of research going on and some breathtaking results or conclusions are drawn, which is most relevant in case of subject like geology.