Reading Comprehension

Source: 800score.com test prep

Japan is making a comeback. After 15 years in a weak economic state, signs of life are finally beginning to show. Deflation is over; prices are no longer falling. Japan is the second largest economy in the world and its recent growth is very good news. The rest of Asia and manufacturers in America will undoubtedly benefit. American consumers had been carrying the majority of the responsibility to keep the global economy moving. Now Tokyo appears to be engaging in real consumption: an indicator that renewal is upon the Japanese economy. Japan's economy barely grew at all in the 1990s. Deflation plagued the country for years with plummeting prices, which reduced wages and corporate income and made debt all the more heavy. Real estate prices fell for 14 years in a row, amounting to a decline of about 60% over that time. The Nikkei index of stock prices fell from an all-time high of 39,000 to below 8,000 before climbing back to about 17,000. It was a bizarre time. Japan lowered interest rates again and again until they hit zero in 2001. Bond prices fell so low that by 2003, even 30-year government bonds yielded less than 1%. Economic historians were known for saying that the cost of borrowing money had never been so low - not in the financial transactions of ancient Greece or Rome or China, or anywhere else in recorded history. And even so, zero interest rates continued. Only now are Japan's bankers talking about the possibly of lifting rates by a quarter of a percent in the coming months. This month, Japan's central bank finally put a stop to 'quantitative reasoning,' a 50-year old policy of pushing excess money into the financial system. Japan was able to do so because consumer prices have recently begun to rise, slowly but surely. Japan's population is aging and its public debt will continue to trouble the country in the long-term. But in the short term American politicians will almost certainly once again begin fussing about the miracle of the Japanese and complaining about Japan grabbing up U.S. properties.

The overall tone of the passage is one of
A. reserved optimism
B. passionate celebration
C. polite skepticism
D. excessive denial
E. being tolerance
[spoiler]
OA: A
IMO: C[/spoiler]

Can someone clarify my doubt for why C is not a correct answer ?
or Why A is much better than C

Author is optimistic about Japan's come back and has mentioned no. of grim circumstances to emphasize the effort made by Japanese. BUT he also mentions,in last lines, that though worst is over still there are problems as population is again and public debt will continue to trouble.

So it is optimistic but in a reserved manner.

I think you took the grim circumstances mentioned as skepticism but they are mentioned to contrast earlier worst condition to improved situation of Japan.