If the fossil of an organism is found in the deeper layers of Earth then it can be predicted that the extinction of organism has occurred thousand years ago.

The dead and decomposing matter in the soil gets suppressed in the lower strata of the soil which turn into fossils due to pressure and temperature in the lower strata of the earth crust. Age of fossils can be detected by the quantity of radioactive carbon compound. Radiocarbon dating is used for determining the age of an object containing organic material by using the properties of radiocarbon (14C), a radioactive isotope of carbon. 

Fossils are organic products which are conserved in the Earth's crust. This means that the fossil is usually formed on or under the Earth's surface or under the water. In other words in the biosphere (think about the biosphere limits). Then this organic material is covered by debris and etc. and becomes the fossil material. The sedimentary rocks are the one type which can contain fossils because these rocks are formed on the Earth surface, under the water etc. In other words, the biosphere can only interact with the sediments. 

Fossils are remains of dead plants and animals. When plants and animals die, their bodies are buried inside the soil. the older the fossils, earlier they must have been buried inside. Year after, many bodies must have got deposited over them. So deeper the fossil layer, older it must have been.

Archeopteryx is a connecting link between reptiles and aves. It has large wings, and hollow bones like aves, and tail and legs like a dinosaur. Apart from these reptilian features, they also have abdominal ribs resembling reptiles. 

Its fossils (some teeth, skull cap and femur bone) were found in 1891 by a Dutch anatomist, Eugene Dubois on the bank of Solo river in Eastern Java.




 

ESA is a more precise technique than previously used techniques for the dating of fossils. It is based on the principle of resonance due to electrons and electron deficient centres produced as a result of emission by naturally occurring radioactive elements in a sample. DNA is the information macromolecule in a living system and can be extracted from fossils or other ancient samples. The sequence information in such a DNA can be compared against sequence information of DNA in other samples or living plants and animals, leading to valuable information about the evolution of plants and animals.

All these (coelacanth, limulus and sphenodon) are  representative of its own kind hence called living fossil.

Fossils are formed in a number of different ways, but most are formed when a plant or animal dies in a watery environment and is buried in mud and silt. Soft tissues quickly decompose leaving the hard bones or shells behind. Over time sediment builds over the top and hardens into rock.

Petrified fossils:- In geology, petrifaction or petrification is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals.

Permineralization:- A process of fossilization in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue.

Ginkgo biloba is a living fossil because its ancestors are unchanged for the  last many hundred years, while its relatives disappeared.

From the given methods, the relatively most accurate method for dating of fossils is electron-spin resonance method. This method is based on the principle of measuring the number of charges occupied by the deep traps crystal band gap.

Fossils are the preserved remains of previously living organisms or their traces, dating from the distant past. Fossils document the existence of now-extinct species, showing that different organisms have lived on Earth during different periods of the planet's history. They can also help scientists reconstruct the evolutionary histories and ancestry of present-day species. For instance, some of the best-studied fossils are of the horse lineage. Using these fossils, scientists have been able to reconstruct a large, branching "family tree" for horses and their now-extinct relatives. 

Impressions are two-dimensional imprints of an organism that doesn't contain any organic material. An impression is a clue left of the organism's biological activity, they can be formed while the organism was moving or any other biological activity.
So the correct option is 'Impressions'.

Chicago Pile 1 was the world's first nuclear reactor, built in 1942 by Nobel Prize winner Enrico Fermi. The reactor was built underneath the University of Chicago's Stagg Field football stadium. On Dec. 2, 1942, Enrico Fermi and 48 of his colleagues succeed in achieving in this reactor the world’s first man-made controlled nuclear chain reaction, thereby establishing the ability of mankind to control the release of nuclear energy. 

Aegyptopithecus was an early primate that existed around 30 mya and it is widely believed to be ancestral to monkeys (cercopithecoids), as well as to humans and apes (hominoids). About 15 mya, primates called Dryopithecus and Ramapithecus were existing. They were hairy and walked like gorillas and chimpanzees. Ramapithecus was more man-like while Dryopithecus was more ape-like.