4)? PASSAGE PASSAGE PASSAGE After decades of being on the back burner owing to costs far outweighing benefits, deep sea mining is now emerging as a serious threat to the stability of ocean systems and processes that have yet to be understood well enough to punish in good conscience their large-scale destruction. Critical to evaluating what is at stake are technologies needed to access the deep sea. The mining company, Nautilus Minerals, has invested heavily in mining machinery. However, resources needed for independent scientific assessment at those depths are essentially non-existent. The role of life in the deep sea relating to the carbon cycle is vaguely understood, and the influence of the microbial(微生物) systems (only recently discovered) and the diverse ecosystems in the water column and sea bed have yet to be thoughtfully analyzed. The principle of exploiting minerals in the deep sea is based on their perceived current monetary value. The living systems that will be destroyed are perceived to have no monetary value. Will decisions about use of the natural world continue to be based on the financial advantage for a small number of people despite risks to systems that maintain planetary stability -- systems that support human survival? The IUCN (International Union for Conservation of Nature) World Conservation Congress helps set in motion some significant and very timely actions that could help blunt the sharp edge of enthusiasm for dividing up the deep ocean. Whatever it takes, there must be ways to elevate recognition of the critical importance of intact natural systems. We need technologies to access the deep sea to independently explore and understand the nature of Earth's largest living system. But most importantly, we need the will to challenge and change the attitudes, traditions and policies about the natural world that have driven us to burn through the assets as if there is no tomorrow. This "as if" can be a reality -- or not -- depending on what we do now. Or what we fail to do. However, there is undeniably cause for hope: there is still time to choose.

【单选题】What does the author mean by saying "blunt the sharp edge of enthusiasm" (Para. 4)? PASSAGE PASSAGE PASSAGE After decades of being on the back burner owing to costs far outweighing benefits, deep sea mining is now emerging as a serious threat to the stability of ocean systems and processes that have yet to be understood well enough to punish in good conscience their large-scale destruction. Critical to evaluating what is at stake are technologies needed to access the deep sea. The mining company, Nautilus Minerals, has invested heavily in mining machinery. However, resources needed for independent scientific assessment at those depths are essentially non-existent. The role of life in the deep sea relating to the carbon cycle is vaguely understood, and the influence of the microbial(微生物) systems (only recently discovered) and the diverse ecosystems in the water column and sea bed have yet to be thoughtfully analyzed. The principle of exploiting minerals in the deep sea is based on their perceived current monetary value. The living systems that will be destroyed are perceived to have no monetary value. Will decisions about use of the natural world continue to be based on the financial advantage for a small number of people despite risks to systems that maintain planetary stability -- systems that support human survival? The IUCN (International Union for Conservation of Nature) World Conservation Congress helps set in motion some significant and very timely actions that could help blunt the sharp edge of enthusiasm for dividing up the deep ocean. Whatever it takes, there must be ways to elevate recognition of the critical importance of intact natural systems. We need technologies to access the deep sea to independently explore and understand the nature of Earth's largest living system. But most importantly, we need the will to challenge and change the attitudes, traditions and policies about the natural world that have driven us to burn through the assets as if there is no tomorrow. This "as if" can be a reality -- or not -- depending on what we do now. Or what we fail to do. However, there is undeniably cause for hope: there is still time to choose.

• A. Put a stop to the deep sea mining projects.
• B. Solve the conflicts among deep sea miners.
• A.Cool down the craze of deep sea exploitation.
• D. Recognize the enthusiasm towards the ocean.