Respuesta :
Core nations is the answer.
Core nations are nations that are relatively highly industrialized of which peripheral countries and semi-peripheral countries depend on.
I've pasted an image of the core, peripheral and semi-peripheral countries so you can make your own assumptions about these.
Hope it helped,
Happy homework/ study/ exam!

Answer:
Option A, Core peripheral nations
Explanation:
Core peripheral nations are those which are extremely rich and carry out industrial activities on a large scale and both the peripheral and semi-Peripheral nations depend on them. Since these core peripheral nations are heavily industrialised, they produce large amount of industrial pollution which consists of greenhouse gases such as carbon dioxide, carbon monoxide , sulfur dioxide etc.
Hence option A is the correct answer.