Final answer:
The president can use a pocket veto to reject a bill without publicly vetoing it.
Step-by-step explanation:
The option that the president can use to reject a bill that has been passed by both houses of Congress without publicly vetoing the bill is the pocket veto. A pocket veto occurs when the president does not sign the bill within the last 10 days of a session of Congress and Congress adjourns during that period. The bill is essentially killed and does not become law.
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