Why B?

Hello @Minerva, We are looking for the answer choice which is contradicted by the evidence obtained from pollen analyses as presented in the passage. Lines 21-31 of the passage state that pollen analyses from Long Lough in County Down revealed "significant patterns" of cereal-grain pollen from approximately 400 AD on. Originally, historians thought that the high clay content of the soils in County Down made cultivation too difficult. They believed that these soils were not tilled until the moldboard plough was introduced to Ireland in the seventh century. The cultivation of cereal grains requires that soils are tilled. Therefore, the fact that significant patterns of cereal-grain pollen were found that dated back to the year 400 AD contradicts the previously held view that "in certain parts of County Down, cereal grains were not cultivated to any significant extent before the seventh century." Hope this is helpful! Please let us know if you have any further questions.

Thanks Victoria, this was very helpful Victoria!

@Minerva happy to help! Let us know if you have any more questions.