What do we learn about Byrd's personal character from paragraph 57? 57. . . . Well, it's done. We have seen the Pole. McKinley, Balchen, and June have delivered the goods. They took the Pole in their stride, neatly, expeditiously, and undismayedly. If I had searched the world, I doubt if I could have found a better team. Theirs was the actual doing. But there is not a man in this camp who did not assist in the preparation for the flight. Whatever merit accrues to the accomplishment must be shared with them.

For this question, it is a little tricky because of the presented options as answers. Single-gene and chromosomal are both types of hereditary disorders and also are one of the most common ones. Complex can be referred to as multifactorial and duplex might be referring to two single-genes, which might be something rare since it isn't an actual type of hereditary disorder. The answer to this question would most likely be A. single-gene and chromosomal. Choosing all of the above would also mean choosing what isn't true, so A. would be the most likely correct one.

I hope this is the answer that you are looking for and it comes to your help.