Final answer:
Australia has lost approximately 30 mammal species in the last 200 years due to human impacts, which corresponds to answer D) 35 in the multiple-choice question.
Step-by-step explanation:
Australia has experienced significant loss of biodiversity over the last 200 years with a notable number of mammal extinctions. Historically, human impact has been a major factor in these losses. Analyses of historical data and extinction rates suggest that Australia has lost about 10% of its mammal species since European settlement, which translates to approximately 30 mammal species. This indicates that the correct answer to the multiple-choice question is D) 35. It is important to note that threatened species may still exist but are at risk of extinction if protective measures are not taken.