Sentence:  The P.D.I. and later the Popular Movement protected the Istiqlal 's `` privileged position '' until the fall of Balafrej , and then the Istiqlal used the same <WSD>argument</WSD> , which it had previously ignored , against the pro U.N.F.P. tendencies of the Ibrahim government . 
Meaning of the word marked with <WSD> tags:  a fact or assertion offered as evidence that something is true