Correct Answer: He exclaimed that it was a fine piece of architecture.

Solution : The correct choice is the fourth option.

The indirect form, also known as reported or indirect speech, involves reporting what someone else has said without quoting their exact words.

The steps of conversion are as follows:

• The reporting verb "exclaimed" remains the same, indicating the emotion or exclamation of the speaker.
• The word "that" is used to introduce the reported clause.
• The pronoun "it" is changed to "that" to maintain grammatical coherence.
• The present tense "is" in the direct speech is changed to the past tense "was" in the indirect speech.

Therefore, the indirect form would be: " He exclaimed that it was a fine piece of architecture."