A、Money. B、Credit. C、Debit card. D、Credit card. D整篇文章用设问句开头“学生办信用卡到底好不好”，接着分别阐述学生办信用卡的好处和坏处，同时还提出了解决方案和办卡的注意事项，故可知本文的主题是信用卡，故本题答

(29)A student credit card? Is it right for me, and can it help me pay for expenses online such as online courses, music, language-learning materials, or even a degree?
     Actually, the answer might be yes or no, depending on your circumstances. Of course, probably the best advice is to save up and then make purchases with cash. Unfortunately, different online services often require a credit card. Here are some. ideas to getting a credit card. First of all, obtaining a student credit card is becoming easier, and many companies are offering such cards to students in this growing market. From a student’s perspective, it allows a person to pay for things online that only can be purchased on credit. (30)Furthermore, it can help students build a good credit history that is often needed later for bigger purchases like a car or home.
     Inspite of these advantages, students have to be careful because interest rates on such cards are often higher and have higher penalties if you fail to pay on time. Furthermore, students may spend well beyond their means and end up in debt that they can’t pay off.
     Perhaps a happy medium is for students to get a debit card that has a credit limit, and money for purchases is just deducted from existing funds from a student’s account. Thus, it operates like a checking account, and (31)when the student’s spending reaches the credit limit, they can’t continue to spend.
     Before you decide to get a student credit card, look carefully at the agreement terms for each company and compare the advantages and disadvantages of each. Searching the Internet for such offers will give you a good start on what to look for in a company.