Mexican leaders post-revolution sought to protect democratic rule primarily through the approval of a new constitution in 1917, which laid the groundwork for various reforms. This constitution addressed issues such as land distribution, labor rights, and national sovereignty over foreign investment. Complementing this, they also initiated free education and worker protection laws to foster a democratic society. ;
Mexican leaders primarily sought to protect democratic rule after the revolution through the approval of the new Constitution of 1917, which included vital reforms in land distribution, labor rights, and education. This constitution aimed to support an equitable society and prevent authoritarianism. Thus, the correct answer is D. They approved a new constitution.
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