The Tables Below Give the Numbers of Some Species of Threatened

question 15

Multiple Choice

The tables below give the numbers of some species of threatened and endangered wildlife in the United States and in foreign countries in 2003. Let A represent the matrix that contains the number of each of these species in the United States in 2003 and B represent the matrix that contains the number of each of these species outside the United States in 2003. Find the matrix B - A. What do the negative entries in matrix B - A mean? ​
​

• A) ​ The negative entries tell us that that particular species is extinct.
• B) ​ The negative entries tell us how many more endangered or threatened species are in foreign countries.
• C) ​ The negative entries tell us that there are more endangered or threatened species in foreign countries.
• D) ​ The negative entries tell us that that particular species is extinct.
• E) ​ The negative entries tell us how many more endangered or threatened species are in the United States.

---

Definitions:

Psychosurgery

A medical procedure that involves operating on the brain to treat mental illness or abnormal behavior, now rare due to advancements in psychiatric medication and therapies.

Trephining

Trephining, or trepanation, is an ancient surgical intervention that involves drilling or scraping a hole into the human skull, historically performed for medical and ritualistic purposes.

Antipsychotic Drugs

Medications used to treat symptoms of psychotic disorders, such as schizophrenia and bipolar disorder, by altering brain chemistry.

Deinstitutionalization

The process of reducing or eliminating reliance on institutional care (like psychiatric hospitals) for individuals with mental illness in favor of community-based services.