【正确答案】 B

【答案解析】[解析] 题意：我们主要从互联网上获得信息。
划线词derive意为：源于，得自。
A项deprive意为：使丧失，剥夺；例：The law deprives criminals of their right to vote.法律剥夺了罪犯的选举权。
B项obtain意为：获得；例：You can also obtain knowledge through practice.你还可以从实践经验中获得知识。
C项descend意为：下降，下去；遗传；例：They descended from the mountaintop.他们从山顶下来。
D项trace意为：追踪；探查；例：We are currently trying to trace the whereabouts of certain sums of money.我们目前正试图找到那几比钱的下落。故选B。