Answer:
D. “In truth, the forest elephant may soon become extinct” (Mackler 91).
Step-by-step explanation:
The MLA citation style uses the last name of the author and then the page from where the reference is taken, this when the author has not been mention in the text, also if you are using two authors it should be (Mackler 91; Thomas 120) and if the reference is for two locations it should be (Mackler 82, 91). In this case this is most accurate option.