Unproductive Mis-Conceptions

(Our teacher has just returned a test to us. One of the questions was, “List three forms of birth control.” I’ve only received 2/3 marks for this question.)

Me: “Why did I get marked wrong on this question?”

Teacher: “Because ‘abstinence’ is not a realistic form of birth control.”

Me: “What do you mean, ‘it’s not realistic?’ It’s 100% effective.”

Teacher: “It’s not realistic. You can’t expect people to control their population just by not having sex.”