Question

What important change in the declaration of independence was made by the full continental congress over the objections of thomas jefferson?

Answer 1

The continental congress made 86 changes to Jefferson's draft. 

here is a small sample of the changes that were made 
When in the course of human events, it becomes necessary for a «one» people to advance from that subordination in which they have hitherto remained, «dissolve the political bands which have connected them with another,» and to assume among the powers of the earth, the equal & independant «the separate and equal» station to which the laws of nature and of nature’s god entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the change «separation».