At the turn of the century it is estimated that a student living alone requires on average A$12 000 (Australian dollars)in living expenses for each year of study in Australia. Of course, these costs increase with time.Upon arrival, students should have funds in excess of the average to cover the cost of text books and establishment expenses such as rental payment and basic furniture items. The amount spent on food, recreation, and entertainment expenses will vary according to requirements, budget, and location.Those who are prepared to live in shared accommodation, which may not be suitable for all, might manage on AS 10 000 per year. It is preferable for overseas students whose English is in need of practice to take advantage of living in situations with native speakers whenever possible. However, sharing with friends who are easy to communicate with is probably more sensible at first.The above figures do not include the cost of large non-essential items such as household equipment or a car. Owning and maintaining a motor vehicle is expensive in Australia. Insurance is compulsory and costly, and parking both on and off campus can be a problem requiring additional expense. It is not advisable for a student to own a car unless it is absolutely necessary. A reasonable second hand car can cost more than A$4 000.Educational institutions are almost always serviced by reliable public transport. The university and college campuses within the major cities are well served by public buses. In addition, the larger cities have extensive train systems. For example, in Sydney, most college and university campuses are only 10 or 20 minutes from a rail station. What does the sentence "Of course, these costs increase with time" (Para. 1)mean（）

A. Costs of education will rise in the future.
B. Costs of living expenses will rise in the future.
Costs of living expenses never decrease in the past.
D. The longer you study in Australia, the more you will spend.