Which natural process is responsible for ridge push: A) Seafloor spreading
B) Mantle convection
C) Subduction
D) Reversal of Earths magnetic field.

I want real answers with EXPLANATIONS.
I will crown the first answer.

People keep spending additional units of a particular resource on a want until their marginal benefit is  decreasing withgreater thanless thannot affected by  their marginal cost.

This is a 2017 topographic map of puerto rico in the united states, and i'm sorry that people there have suffered such a disaster. i want to ask, what do the yellow dots and areas represent on this graph? and the blue area and the little blue circle, and the little blue sign that looks like a signal tower, what do they stand for?

Soil is made of air water organic material minerals weathered rock