When ancient oak planks were unearthed during subway construction in Rome, Mauro Bernabei and his team examined the growth rings in the wood to determine where these planks came from. By comparing the growth rings on the planks to records of similar rings in oaks from Europe, the team could trace the wood to the Jura region of France, hundreds of kilometers from Rome. Because timber could only have been transported from distant Jura to Rome by boat, the team's findings suggest the complexity of Roman trade routes.

Which choice best describes the function of the underlined sentence in the text as a whole?

Question

Accepted Answer

It presents a conclusion about Roman trade routes based on the team's findings.

Answer

It questions how the team was able to conclude that the planks were used to build a boat.

Answer

It explains why the planks were made from oak rather than a different kind of wood.

Answer

It describes common methods used in Roman subway construction.