问题如下：
Wang made the following statements about the advantages and disadvantages of the top-down and bottom-up approach
Statement 1: One advantage of the bottom-up approach is that it is easier to gain an informational advantage in individual companies or bonds rather than the overall market.
Statement 2: Another advantage of the bottom-up approach is that it can be easy to earn substantial returns from bottom-up security selection without exposing the portfolio to macro factors.
Statement 3: One advantage of the top-down approach is that sizable portion of credit returns can be attributed to macro factors.
选项：
A.Statement 1 and statement 3 are correct.
B.Statement 1 and statement 2 are correct.
C.Statement 2 and statement 3 are correct
解释：
答案：A is correct.
考点：Top-down, bottom-up方法的优缺点对比
解析：Statement 1和Statement 3正确，为原版书原句。
Statement 2错误，正确的应该为：即便用Bottom-up的方法选择出了合适的个股，Credit returns中很大一部分仍可以归因于Marco factors，Statement 2中，easy to earn a substantial return without exposure to macro factors错误；
原版书原句为：
Because a sizable portion of credit returns can be attributed to macro factors, it can be difficult to earn substantial returns from bottom-up security selection without exposing the portfolio to macro factors.
老师，您好！解答中提到 “Because a sizable portion of credit returns can be attributed to macro factors, it can be difficult to earn substantial returns from bottom-up security selection without exposing the portfolio to macro factors.”。这个意思是说 bottom-up也剥离不了macro factor的影响么？但是讲excess return的时候，不是说hedge了interest rate risk，只是保留credit risk的敞口。bottom-up是基于excess return的话，不应该剥离了macro factor的影响么
