In 1892, the first national convention of the people’s party was held in
a-omaha, nebraska.
b-san francisco, california.
c-philadelphia, pennsylvania.
d-san antonio, texas.

A-Omaha, Nebraska.  

Explanation:

The February 1892 Farmer's Alliance tradition was gone to by present and previous individuals from the Greenback Party, Prohibition Party, Anti-Monopoly Party, Labor Reform Party, Union Labor Party, United Labor Party, Workingmen Party, and many other minor gatherings.

Conveying the last discourse of the tradition, Ignatius L. Donnelly, expressed, "We meet amidst a country conveyed to the skirt of good, political, and material ruin. ... We look to reestablish the legislature of the republic to the hands of the 'plain individuals' with whom it started. Our entryways are available to all purposes of the compass.

The interests of rustic and urban work are the equivalent; their adversaries are indistinguishable." Following Donnelly's discourse, delegates consented to build up the People's Party and hold a presidential naming tradition on July 4 in Omaha, Nebraska. Columnists covering the juvenile party started alluding to it as the "Populist Party," and that term rapidly turned out to be broadly well known.

i also think it is c