What Is the Primary Distinction Between an Interest Group and a Political

What is the primary distinction between an interest group and a political party?

A) Interest groups are smaller than political parties.
B) Interest groups operate at the national level while political parties are organized at the state level.
C) Interest groups do not seek positions of power in government; political parties do.
D) Interest groups are focused on individual issues; political parties are interested in large sets of issues.
E) Interest groups are larger than political parties.