Sentence:  But the real way to build a successful online business is to be better than your rivals at undermining people's control of their own attention. Partly, this is a result of how online advertising has traditionally worked: advertisers pay for clicks, and a click is a click, however it's <WSD>obtained</WSD>. 
Meaning of the word marked with <WSD> tags:  To get hold of; to gain possession of, to procure; to acquire, in any way. (from 15th c.)