Sentence:  On the contrary , even in the heart of `` the Bible belt '' itself , as can be <WSD>attested</WSD> by any one who is called to work there , the industrial and technological revolutions have long been under way , together with the corresponding changes in man 's picture of himself and his world . 
Meaning of the word marked with <WSD> tags:  authenticate, affirm to be true, genuine, or correct, as in an official capacity