At which type of plate boundary would a string of small volcanic islands most likely form?

convergent ocean-ocean boundary
transverse boundary
divergent ocean-ocean boundary
convergent ocean-land boundary

The answer would be "convergent ocean-ocean boundary". Two plates come together and collide, the impact of the collision causes the plates to come out as mountain ranges or in this case a string of small volcanic islands. Hope that helps! :)

i am going to guess that it is co2.