Select the option that best expresses the meaning of the given idiom.

Under wraps

The correct answer is Maintained in secret or concealed from the public.

Explanation:
The idiom "under wraps" means to keep something secret, confidential, or hidden from general knowledge or public view.

Example Sentence:
"The developers kept the new software features under wraps until the annual conference."

Analysis of Options:
• Delayed due to unexpected circumstances: Incorrect. This refers to a delay or postponement rather than keeping something secret.
• Maintained in secret or concealed from the public: Correct. This perfectly matches the meaning of the given idiom.
• Undergoing rigorous safety testing: Incorrect. This refers to quality control or evaluation processes.
• Exhibited publicly for everyone to see: Incorrect. This describes an open display, which is the antonym of keeping something "under wraps".