In case of arrival after the closing time, what must be established regarding the proposal?

The correct choice highlights the fundamental principle that proposals submitted after the closing time cannot be considered for evaluation due to strict adherence to submission deadlines set forth in procurement regulations. This principle is crucial in maintaining fairness and equity among all bidders.

When a procurement opportunity is publicly announced, a deadline is established to ensure that all interested parties have an equal chance to submit their proposals. Accepting late submissions could compromise the integrity of the procurement process, as it might favor one bidder over others who submitted on time. Therefore, the rules clearly state that proposals received after the designated closing time are not eligible for evaluation, reinforcing the importance of timing in the proposal submission process.

This clear prohibition is essential to uphold the competitive nature of contracting and to avoid potential disputes or claims of favoritism, thus ensuring that all participants operate under the same conditions and time constraints.