请用英文回答几个证券投资方面的问题

1.Market efficiency and arbitrage, and their consequences for judging portfolio management performance ?

这个问题是问市场效率和套利空间状况及其对资产组合管理效果的影响，回答可以是

If the market is efficient and there is huge room for arbitrage, the portfolio should be flexible so that it could be adjusted quickly to grasp market chances. Though it may pose challenges for portfolio management, the possibility of achieving high returns is also getting bigger.

2.Use of derivatives (futures and options) in portfolio management; identification of option components in various economic contracts.
这好像不是问题，意思是在资产组合管理中衍生产品（例如期货和期权）的运用以及不同类型合约中期权类别。

Futures and options are very important in portfolio management because derivatives can greatly reduce risk exposure in a given portfolio. In China, no matter in what economic contracts, call option is always the choice as short-selling is still banned in China.

3. International aspects of portfolio management .
这个是说资产组合管理中的国际化因素。

With integration of global financial markets, it is important to put part of the assets in overseas markets to seek higher reduces and to better manage risks. For instance, the yield of U.S treasuries is currently higher than that in Japan, China or EU, and it may be a good choice to include part of US treasuries in an asset portfolio, based upon consideration of other factors such as exchange rate changes.

Since your questions are too general, I would make some arguments from the above ansewr.

1.Market efficiency theory is to say whether all information is available to the market. If market efficiency is in strong form , there is no way to get better return than the market performence, so there's no arbitrage exists. If it is weak form of market efficiency, then there are some potential arbitrages could be obtained. However, portfolio management performance evaluation is not based on the performence of activities in arbitrages. In the semi-strong market efficiency, deversified portfolio management is prefered.