Occupation socialization: refers to the process by which individuals choose occupations according to social needs, master the knowledge and skills to engage in a certain occupation, or update knowledge and retrain skills after engaging in a certain occupation. Which of the following is professional socialization? ['Xiao Zhang is a technical worker in a certain unit. When he sees that there is an urgent need for translation talents in many fields, it is convenient to study in his spare time. After obtaining a translation qualification, he leaves to work for another company.', 'Xiao Liu was assigned to a car class after joining the army and learned superb car repair skills. After retiring, he opened a repair shop by himself.', 'Li, an accountant, loves cooking and took a training class in his spare time to learn about nutrition and improve cooking skills.', 'Xiao Chen accumulated a wealth of knowledge and experience while raising children, and then opened a kindergarten on the advice of friends.']