How many genes found on the Y chromosome trigger the testes to produced testosterone?

After surviving an Amtrak derailment, John experienced frequent, vivid thoughts and images of the accident for several months. He also had problems sleeping and was irritable and withdrawn. John is suffering from ________

a. major depression. b. posttraumatic stress disorder. c. generalized anxiety disorder. d. panic disorder.

Imagine being an older adult. All things being equal, which is the LEAST dangerous driving situation?

A) making a left turn into traffic B) driving at night C) stopping in time when the light turns red D) driving in your neighborhood