D
It is common to consider learning as something that takes place in school, but much of human learning occurs outside the classroom, even from birth and people continue to learn throughout their lives.
Even before they enter school, young children learn to walk, to talk, and to use their hands to use toys, food, and other objects. They use all of their senses to learn about the sights, sounds, tastes, and smells in their environments. They learn how to communicate with their parents, grandparents,    siblings, friends, and other people important to their world. When they enter school, children learn basic academic subjects such as reading, writing, and mathematics. They also continue to learn a great deal outside the classroom. They learn which behaviors are likely to be rewarded and which are likely to be punished. They learn social skills for communicating with other children. After they finish school, people must learn to deal with many major changes that affect their lives, such as getting married, raising children, and finding and keeping a job.
Because learning continues throughout our lives and affects almost everything we do, the study of learning is important in many different fields. Teachers need to understand the best ways to educate children. Psychologists, social workers, criminologists, and other humanservice workers need to understand how certain experiences change people's behaviors. Employers, politicians, and advertisers make use of the principles of learning to affect the behaviors of workers, voters, and consumers.
Learning is closely related to memory, which is the storage of information in the brain. Psychologists who study memory are interested in how the brain stores knowledge, where this storage takes place, and how the brain later outputs knowledge when we need it. In contrast, psychologists who study learning are more interested in behavior and how behavior changes as a result of a person's experiences. 
68. The underlined "siblings" in the second paragraph probably means_______.
A. teachers     B. classmates     C. doctors     D. brothers or sisters
69.  Which period of children's life does they begin to know to behave well according to the passage?
A. After they go into society          B. Before they enter school
C. When they are at school          D. Before they are born
70.  Which of the following is WRONG according to the passage?
A. As a matter of fact, learning begins with formal school education.
B. Teachers need to understand the best ways to educate their students.
C. People need to understand how certain experiences change their behaviors.
D. Employers should study the principles of learning to manage their workers well.
71.  The author mainly tries to tell us_______in the last paragraph.
A. learning is only related to memory and experiences
B. psychologists are interested in how the brain stores knowledge
C. psychologists are more interested in a person's behavior
D. how the relationship between learning, brain and behavior works