In the sentence, certain words are in bold and numbered from A to E, which are the possible pairs to be interchanged. Choose the pair(s) of words which need to be interchanged to make the sentence grammatically correct and meaningful.

El Niño is the weather (A)system in the Pacific that can result in (B)records high temperatures, as it did in 1998, which until 2005 held the (C)crown of the (D)warmest year since (E)unusually began in 1850.