GMAT Sentence Correction (SC) | Re: At issue in the proceeding is whether the gaming firm

At issue in the proceeding is whether the gaming firm can verify that

the site’s users are

over 21 and
in a legal gambling state or country,

using special identification and location software, among other tools.

I could not find anything particularly incorrect with given sentence but was skeptical regarding verb+ing phrase using.
it can modify the whole sentence thereby explaining how gaming firm can verify or imply an effect of sth.

B--can, with the use of special identification and location
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