Which of the following are unique features of Reddit? Select all that apply.

The correct options highlight Reddit's distinct community-centric model and its unique karma system. Unlike traditional social media where user profiles are central, Reddit users primarily subscribe to and engage with subreddits (communities) based on shared interests. This fosters a different kind of interaction and content discovery. The karma system, where users gain points for upvoted content and comments, is a core gamified element that incentivizes positive contributions and engagement within these communities. The incorrect option, "Comments and posts are seen based on algorithms," is not unique; most major social media platforms use algorithms to determine content visibility, making it a common feature, not a differentiator for Reddit.