Seafloor spreading causes the the continents of South America and Africa to move further apart each year. What type of plate boundary cause this crustal feature? A. Subduction
B. Divergent Boundary
C. Convergent Boundary
D. Transform Boundary

Seafloor spreading occurs at divergent plate boundaries.As tectonic plates slowly move away from each other, heat from the mantle's convection currents makes the crust more plastic and less dense.

the correct answers are:

a - pacific plate;

it is the biggest oceanic tectonic plate. surrounded on all sides by continental tectonic plates, it is submerging and gradually becoming smaller and smaller.

b - north american plate;

huge continental plate, occupying big portion of the northern hemisphere.

c -eurasian plate;

alongside the north american plate, it is one of the two dominant continental plates in the northern hemisphere.

d - indian plate;

a small continental plate, that has been part of gondwanaland initially, but after the break up of it, moved towards northeast and pushed into the eurasian plate that was once part of laurasia.