Two production management methods, A and B, have been tried out in two factories respectively. The trial work was carried out as follows: method A was tested in a large factory with a high level of education in the leadership group; method B was tested in a small factory with a low level of education in the leadership group. The result was that the economic benefits of Method A were good, but the economic benefits of Method B were not good. Therefore, it was concluded that Method A was the reason for achieving better economic benefits. All of the following can weaken the above conclusions, except:. ['The situation of the two factories is different, and it cannot be used as an experimental base for testing the two management methods.', "Factory A's leadership team has a high level of education, which is conducive to the understanding and implementation of management methods.", "Factory B's leadership team has a low level of education, which is not conducive to the understanding and implementation of management methods.", 'Comparing method A with method B, in fact, method B is better, but unfortunately, the foundation of small factories implementing this method is too poor.']