At this point we have to consider people who deny that climate change is caused by humans to be climate deniers, since they are advocating for no change in behavior which is the same as people who outright deny that it's happening.
And (b) is not really that we _shouldn't_ change our behavior, but that the most popular ideas for how we should are varying degrees of infeasible, harmful, or fascistic.
The "right" on this issue is largely misunderstood. Those pushing for a shift to renewables and a lifestyle change in wealthier nations deserve better literature on what their opposition is advocating for and against: https://compactmag.com/article/energy-lysenkoism
What is the degree of human causation? How much can be imputed to solar cycles at any given moment of time? What % of CO2 is produced by humanity? Is there a possibility of actual catastrophe? Should pollution reduction and cleanup be prioritized over carbon capture/reduction?