As the activity on a card grows, specific comments can sometimes get lost in the clutter. Can I link to a specific comment?
Unfortunately, there seems to be no way to link to just an activity record inside a card.
The best way to keep a comment visible and near the top is to add the comment to the card description in addition to the activity records.
You can link to a card by using the link found in the "Show Card ID" button on the back of the card.