In the following question, a sentence has been given in Direct/Indirect speech. Out of the four alternatives suggested, select the one which best express the same sentence in Indirect/Direct speech. He said, "How can a Zebra talk?''

• He wondered how a Zebra talks.
• He questioned a Zebra talking.
• He asked how a Zebra could talk.
• He was amazed how a Zebra can talk.