Read the sentence from paragraph 3. Her excitement and wonder about the mysteries of the sea kept her in the water too long.
Which meaning of the word mysteries is used above?

A people who are secretive

B the customs of an ancient
belief system

C movies or books dealing with puzzling crimes

D things that are difficult to understand or explain

D. Things that are difficult to understand or explain.

Explanation:

The word "mystery" refers to the thing(s) difficult to understand or comprehend, or even explain. It suggests things that are hard to be understood or even explained to others, anything that mystifies or is secretive and unable to be understood.

As used in the given sentence, the word "mysteries" refers to the things that are hard to understand, the things in the sea that appeals to her yet are incomprehensible.

Thus, the correct answer is option D.

the correct answer is to reduce tax