Passage Summary: Foreigners can't be cabinet secretaries because that job involves 'citizens-only' tasks. Since undersecretaries have to step in and do the secretary's job sometimes, they shouldn't be foreigners either.

Conclusion: Foreign citizens should not be appointed to the position of cabinet undersecretary.

Reasoning: Cabinet secretaries perform duties reserved for citizens, and undersecretaries must be able to fill in for secretaries; therefore, undersecretaries would eventually perform duties they are not supposed to perform.

Analysis: This is a 'Complete the Argument' task that requires a logical deduction based on the provided rules. We are told that no one should hold a position if it involves duties they shouldn't perform, and that undersecretaries must perform the duties of secretaries. Since secretaries perform duties that foreign citizens shouldn't perform, the logical chain dictates that foreign citizens shouldn't be undersecretaries. Look for an answer that bridges the gap between the restrictions on the secretary role and the requirements of the undersecretary role.