Which boundary produces lava but no volcanoes?

Convergent boundary is the boundary that produces lava but no volcanoes.

Explanation:

A volcano is a fracture in the crust of any planet which can allow hot gases, volcanic ashes, and lava to flow out and escape from the core of the planet. On Earth, such fractures or rupture are usually found where the tectonic plates are converging or diverging.

Volcanoes are also mostly found underwater. The boundary that produces lava but no volcanoes is convergent boundary. One tectonic plate slides beneath the other plate causing subduction. When the lava makes contact with the surface, they make volcanic arcs.