Deforestation is one of the biggest environmental threats to the ecological balance in the world10/15Mark the letter A, B, C, or D to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. Question. Deforestation is one of the biggest environmental threats to the ecological balance in the world.suretiescertaintiesdangerssafetyGiải thíchĐáp án C Threat = danger (mối nguy hại)