The passage is mainly about ___________

Câu hỏi: Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
Employees in many countries change jobs more often than previous generations of workers. They don't expect to find a job with a company that will take care of them for the rest of their lives. But what is the cause of this trend? Is it a new economy, new ways of doing business, or the employees themselves?
A more globalized economy has had an effect on employment. A large number of companies are now international, and one of them may decide that moving from its offices from Germany to Poland, for example, is in its best interest. That means employees who live and work in Germany may be asked to relocate their families to a new country or be told that their jobs are simply eliminated.
Companies have also responded to economic pressure by restructuring for greater efficiency. This sort of change within a company usually means that unnecessary jobs are cut, or that fewer employees must do more work. In their case, some employees find themselves looking for new jobs.
New technology has also had an impact on workplaces. The increasing use of personal computers has meant fewer jobs for office secretaries, as their former bosses do their own words processing and letter writing, and for travel agents, as more travelers make their own reservations online. Automation, including the use of robotic devices, has replaced workers in clothing factories, post offices, and telephone companies, to name just a few.
Besides these economic and technological reasons, today's employees are also responsible for more frequent job changes. Workers in the past were less likely to leave a company because they were dissatisfied with working conditions or because they didn't get along well with their fellow employees. People today expect to enjoy their work and have personal satisfaction from what they do for a living.
Employees may also leave a job because they have learned all they can learn from their current job. Getting a new job means gaining new skills and making new contracts, and these skills and relationships could bring them a step closer to their "dream job", the one that is challenging, emotionally and financially rewarding, and preferably closer to home or their children's school.
Finally, companies start up and close down more quickly than they once did. Employees who suspect that their employer is not doing well may decide to start looking for a new position before the company
closes its doors.
(Source: Active Skills for Reading: Book 2 by Neil J. Anderson Thompson)
The passage is mainly about ___________
A. reasons companies aren't taking care of employees as they once did
B. ways in which international companies have caused a loss of job
C. reasons employees change jobs more frequently than they did in the past
D. the contrast between employers of the past and employers nowadays