Final answer:
The key aspect of Jacksonian Democracy development was the end to property qualifications for voting, ultimately leading to Andrew Jackson's victory in the 1828 election.
Step-by-step explanation:
A significant part of the development of Jacksonian Democracy in the 1820s and 1830s was B) an end to property qualifications for men to vote in almost all states. This was a major political innovation of the early nineteenth century, which expanded the electorate and reflected the growing democratic spirit of the era. The most notable example of this expansion was in the overwhelming victory of Andrew Jackson in the 1828 election, where he captured a majority of both the popular and electoral votes, signaling a shift towards a more inclusive democracy that focused on the common man.