Which of the following incomes would be taxed the LEAST?

a$.$

An ordinary dividend for an investor who is in the $12\%$ marginal tax bracket.

b$.$

A long term capital gain for an investor who is in the $12\%$ marginal tax bracket.

c$.$

A short term capital gain for an investor who is in the $12\%$ marginal tax bracket.

d$.$

Bond interest for an investor who is in the $12\%$ marginal tax bracket.