Bounty or Airdrop? what is the most easiest way to earn tokens?
You should probably look up first the difference betwixt the two.
Airdrops: Usually you just need to give your wallet's address for them to send you coins. They're free coins.
Bounty: Bounty Campaigns on the other hand would require more of you-- following certain guidelines. Doing services such as signature campaigns, social media campaigns, ANN (Announcement) and White paper translations, etc. Your reward would depend on your contribution.
Airdrops are somewhat risk free and you get less but free coins. Bounties would require you to do services and oftentimes failure to conform to their guidelines would prevent you from getting any coins altogether, it could also take them months to finish a campaign.
EZ Money? = Airdrops
Hardwork and patience = Bounties.