There is no single cause of climate change; several factors ...

There is no single cause of climate change; several factors such as greenhouse gas emissions,deforestation,and human activities have come together to        the issue.（ ）

本题句意为“气候变化不是单一的原因；温室气体排放、森林砍伐和人类活动等几个因素共同加剧了这一问题。”deceive：欺骗；relieve：减轻，缓和(不快或痛苦)；exacerbate：加剧，使恶化；tangle：使缠结。根据句意，选C。