In this task you will be given a process, and a question. The process contains a sequence of steps that happen in order. The question asks about the effect of a certain event on another event. If the first event has a positive effect on the second event, answer with "for", if it has a negative effect, answer with "against". If there's no causal relationship between the two, answer with "none".
Q: Process:  -Greenhouse gases are released into the air by human activities -The earth changes energy from the sun into heat -Heat rises from the ground -Greenhouse gas molecules in the atmosphere prevent the heat from going into space -The temperature of the earth increases -The temperature continues to rise and melts the polar ice caps -The temperature rises even faster.
 Question: What is the effect of people buy more cars and boats on less greenhouse gas molecules prevent heat from going into space.?
A: 
against