In most developed countries, when you put money in the bank, the government guarantees that you can get your money back even if the bank fails. That means you're safe no matter what happens. Most people feel more secure that way. But financial events in recent, years have made clear that this guarantee, known as “deposit insurance,” carries dangers as well as benefits. As a result, many governments are still debating how to regulate banks. To understand the problem with deposit insurance, imagine you are a banker. Let's say your bank has $1 million in deposits. You could use that money to make a loan at a high interest rate to a risky company. If you get lucky and the risky company pays back the loan, your bank will make a big profit. Or, you could make a loan to a very stable company at a lower interest rate. This way is safer, but your bank will make only a small profit. Under the system of deposit insurance, a banker will typically make the loan to the risky company. He will think to himself as following : “ If the loan is paid back, my bank will make a lot of money. And even if the company fails to pay, we still won't have any problem because we can get $1 million through deposit insurance to pay back our depositors.” But if the deposit insurance system runs out of money, the government must get the $1 million from taxes that average citizens pay. One economist uses the analogy of a coin toss to criticize the system: “If it's heads, the bank wins. If it's tails, the taxpayer loses,” In other words; deposit insurance gives banks an incentive to take big risks in the hopes of making big profits. And it could cause taxes to rise if the government has to spend a lot of money bailing out failed banks. The U.S. savings-and-loan problem of the 1980s illustrated this point. A “savings-and-loan” institution is a kind of bank that accepts deposits and then lends the money out, primarily to individuals. But during the 1980s, many of these institutions made dangerous loans to real estate developers. They ended up losing billions of dollars. Eventually, the U.S. government had to spend $170 billion in taxpayers' money cleaning up the problem. What can be done? One solution applied in many countries is tighter regulation and control of banks. Governments in these countries monitor banks closely and make sure they are not acting recklessly. However, this method isn't ideal because it restricts the free activity of banks. It's hard to run an efficient bank if government officials are always looking over your shoulder. Some economists take an extreme view. They say the government should end deposit insurance and leave it up to individual savers to judge whether their bank is safe. However, one might reasonably ask whether average people can be expected to understand banks' balance sheets and choose their bank accordingly. As of now, therefore, this dilemma of banking regulation remains unsolved.
補足説明 However, one might reasonably ask （whether average people can be expected to understand banks' balance sheets and choose their bank accordingly.）
（ ）→ 普通の人が企業のバランスシートを理解して、accordinglyそれに応じて, 銀行を選ぶことができるかどうか、 話は一旦変りますが、小学生に高校生の数学の問題を解けと言ったら、「こんな難しい問題を小学生が解くことを期待するんですか？」という質問をされました。この子の質問（＝反論）はreasonable(妥当)でしょうか。 妥当ですよね。そんなものを解かせようとするほうがおかしい。実はこの子の質問は形的には質問ですが、内容的には否定文つまり、「こんなの解けるわけないでしょ！」です。英文のほうもこれと同じで、作者は（ ）内のことを否定、つまり、そんなことできない、と思っているわけです。ですから、そういう質問（＝反論）がでるのはreasonable(妥当、無理からぬこと)なので、reasonably ask と言っているのです。
As of now, therefore, this dilemma of banking regulation remains unsolved. 現在のところ、このジレンマ（銀行を規制してもしなくても問題が生じる）は解決されないままだ。