Which of the Following Best Defines the Term Best Efforts

Which of the following best defines the term best efforts underwriting?

A) Underwriter sells as much of the issue as possible, but can return any unsold shares to the issuer without financial responsibility.
B) Financing for new, often high-risk ventures.
C) A group of underwriters formed to reduce the risk and help to sell an issue.
D) Loans made by a group of banks or other institutions.
E) Direct business loans of, typically, one to five years.