Analyze the relationship between 'pure' and 'channel' within the context of the input sentence.
Options: original broadcaster, founded by, product/material produced, headquarters location

So we're very first all of our channel checks that ophthalmologists are seeing Rhopressa and Rocklatan as the pure indications to some of the existing generic options, but we're also hearing prescribers are facing some challenges because you've been in cases where Rhopressa and Rocklatan are indicated as covered by a plan.
original broadcaster