参考答案

正确答案：D
解析：是非题型见第三段第二句：As is the case for so many threatened species, the breakup of their habitat sounded the death knell for tamarins，depriving them of the continuity of forest they require to remain abundant and safe from potential threats in any single vicinity. (正如许许多多濒危物种一样，绢毛猴们赖以生存的生活环境的崩溃为他们敲响了丧钟，任何一块聚居地的潜在威胁也剥夺了他们保持大量种群和安全所需的连片的森林)；因此选项A，B，C中提到的食物短缺、潜在威胁的逼近及原本为逃避那些食肉动物在树上生活所需的连片森林都是原因，因此D为答案。