Antonym of 'trivial'

The same question, asked 2 times: 19 Jul 2023 S4*, 27 Jul 2023 S1. Every wording below, oldest first.

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Question 1
19 Jul 2023 S4
83 $Select the most appropriate ANTONYM of the underlined word. Trivial issues have always interested our boss.$
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Question 2
27 Jul 2023 S1
82 $Select the most appropriate ANTONYM of the given word. Trivial$
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