Correct Answer: David asked whether someone could explain what was going on.

Solution : The correct choice is the first option.

Indirect speech, also known as reported speech or indirect discourse, is a way of reporting what someone else has said without quoting their exact words.

Narration conversion:

• The reporting verb "said" is changed to "asked".
• In yes-or-no questions, the connector "if/whether" is used to introduce the reported clause in order to convert the questions into statements.
• The present tense "is" is changed to the past tense "was".
• The modal verb "can" is changed to "could".

Therefore, the correct answer is: David asked whether someone could explain what was going on.