The similarities between "farmers who applied to join agricultural production cooperatives" in 1950s and "farmers who accepted production contracts" in 1970s and 1980s are as follows.

This question is multiple choice. According to the analysis of the knowledge learned, it can be seen that in the 1970s and 1980s, farmers engaged in contracting under the premise of insisting on public ownership, and did not change the ownership of the means of production, so item A was excluded. In cooperatives, farmers have no autonomy in production and distribution, and at this time they are far from becoming an industrialized power. B and c can also be excluded.