Which of the following is an exception to full and open competition?

This choice describes a situation where competition may be limited, but it does not constitute an exception to full and open competition. Instead, it indicates a scenario where the agency has determined that only two sources can fulfill the requirement, which still involves a competitive process, albeit restricted in scope.

While urgency can lead to expedited procurement processes, it does not serve as a categorical exception to full and open competition. Agencies may use expedited methods to meet urgent needs but are still required to follow competitive procedures unless a specific exception applies.

This option refers to situations where a follow-on contract is awarded to a contractor who has previously performed well on a related contract. Although this can limit competition, it does not inherently exempt the process from the principles of full and open competition, as it often requires justification and still aims to encourage competition.