Adele's '25' continues reign atop Billboard 200 chart

By Piya Sinha-Roy LOS ANGELES (Reuters) - British singer Adele once again kept her reign at the top of the weekly U.S. Billboard 200 album chart on Monday, holding off albums by Rihanna and Justin Bieber. Adele's "25, the top-selling album of 2015, notched another 100,000 units last week in album and song sales and streaming activity, according to figures from Nielsen SoundScan. R&B singer Rihanna's latest album "Anti" climbed one spot to No. 2 with 80,000 units sold, while Canadian pop star