Consider the following draft of a passage about marine biology:
[1] __________________________________________________ [2] In December 1938, Marjorie Courtenay-Latimer, a curious museum curator in East London, South Africa, received a call from a local trawler captain who had brought in an unusual catch. Amid the pile of sharks and rays, she noticed a strange, five-foot-long fish with thick, iridescent blue scales and lobe-like fins that resembled limbs. Sensing its importance, she brought the specimen to her museum and contacted ichthyologist J.L.B. Smith. Smith famously identified the fish as a coelacanth, a primitive species previously known only from fossils dating back to the Cretaceous period.
This 'living fossil' provided biologists with a rare opportunity to study a creature whose anatomy had remained virtually unchanged for millions of years. Its lobe-like fins, which contain bones arranged similarly to those in land vertebrates, offered a direct physical link between ancient fish and the first tetrapods that crawled onto land. The discovery not only filled a massive gap in the fossil record but also prompted scientists to reconsider how species adapt over vast spans of geological time.
Which choice, if added at [1], provides the most effective introduction to the passage by establishing its central thesis?
- ACurators of natural history museums frequently rely on commercial fishing fleets to find specimens, they must examine daily catches carefully.
- BAlthough the coelacanth was long assumed to have vanished from the Earth along with the dinosaurs during the Cretaceous period.
- The unexpected discovery of the coelacanth in the twentieth century upended the scientific consensus on extinction and provided a living window into evolutionary history.Answer
- DWhile many prehistoric marine creatures are known only through fossilized remains, the classification of these ancient specimens are highly debated by ichthyologists.