Which of the Following Items May Not Be Subject to the Self-Employment

Which of the following items may not be subject to the self-employment tax?

A) A partner's distributive share of partnership business income
B) Amounts paid to an independent contractor who is the sole proprietor of his company.
C) Amounts paid to a consultant who is the sole proprietor of his company
D) Rental income from apartments owned by an individual whose regular source of income is wages and salaries.
E) Amounts received by an author as royalties from a book he wrote.