The sentence that is in passive voice is:
"The news of their granddaughter's birth thrilled the Kirbys."
Explanation:
1. In passive voice, the subject of the sentence is acted upon by the verb.
2. In the sentence "The news of their granddaughter's birth thrilled the Kirbys," the news (subject) is the one doing the action (thrilled), which is not in line with the passive voice structure.
3. The active voice sentence would be: "The Kirbys were thrilled by the news of their granddaughter's birth," where the Kirbys (subject) are being thrilled by the news (object).
4. Therefore, the correct answer is the second sentence as it is in active voice, not passive voice.
