Which of the following is an important characteristic of professionals who typically support the Democratic Party?

The support for the Democratic Party by individuals who are members of labor unions stems from the historical ties between the party and organized labor. The Democratic Party has traditionally advocated for workers' rights, fair wages, and inclusive labor policies, which resonate strongly with unionized workers. Labor unions often focus on collective bargaining to negotiate better conditions for their members, and they tend to align with the Democratic Party due to its policies that protect and promote these interests. This alignment is also reflected in the party's broader commitment to social equity and economic justice, values that labor unions uphold.

Individuals in the other categories, such as small business owners, investment bankers, and technology entrepreneurs, may not inherently share the same priorities or values that align with the Democratic Party’s platform. Small business owners can be supporters of either party, largely depending on their individual values and specific economic concerns. Investment bankers and tech entrepreneurs often have interests that may not coincide with the labor-focused congressional agenda traditionally championed by the Democrats.