Answer:
Parts 2, 3, 4 and 5 show the attitudes and comments made by the White family about the major’s story and the alleged powers of the monkey’s paw.
In part 2, Mrs. White compares the major’s story with the ‘Arabian nights’ so as to show that, for her, it was nothing more than a tale. In addition, she makes a scornful comment about the seriousness of the situation.
In part 3, the overall veracity of the major is questioned, indicating the lack of trust in his words.
In part 4, a sarcastic comment about the odds of the wishes coming true is made by Herbert, which indicates his skepticism about the paw’s powers.
In part 5, Mr. White’s doubtfulness is literally expressed in the text.
The remaining part (part 1) is the only one that shows the words of the major himself. Thus, it is self-evident that this is the only part that will not express doubts about his story.