og 19-787

crystal_10

【OG19-P723-787题】

The World Wildlife Fund has declared that global warming, a phenomenon most scientists agree to be caused by human beings in burning fossil fuels, will create havoc among migratory birds by altering the environment in ways harmful to their habitats.

• A
  
  a phenomenon most scientists agree to be caused by human beings in burning fossil fuels,
  
  
  
• B
  
  a phenomenon most scientists agree that is caused by fossil fuels burned by human beings,
  
  
  
• C
  
  a phenomenon that most scientists agree is caused by human beings’ burning of fossil fuels,
  
  
  
• D
  
  which most scientists agree on as a phenomenon caused by human beings who burn fossil fuels,
  
  
  
• E
  
  which most scientists agree to be a phenomenon caused by fossil fuels burned by human beings,
  
  
  

正确答案为c。
对于这道的题目的正确答案没有啥疑问。
只是看到有人解析说 快速判断 AB是错误的一条依据是  同位语从句的连接词that不可省，所以a phenomenon后应加上that，想请问大家同位语从句在语法上有这条规定？不能省略that这条是绝对的吗？

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