question:  Which of these is a reason that Mary would have wanted Sammy to replace Phil?
context: Transcriber's Note: This etext was produced from Astounding Science Fiction December 1955. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed. Phil Conover pulled the zipper of his flight suit up the front of his long, thin body and came into the living room. And the faint lines around his dark, deep-set eyes were accentuated when he smiled at his wife. His wife was sitting stiffly on the flowered couch that was still not theirs completely. Then she leaned forward and crushed the cigarette in the ash tray on the maple coffee table and took another from the pack. Yes, I'm sure you did," she said, finishing the ritual; but her voice broke, and she turned her head away. Phil sat beside her and put his arm around her small shoulders. If anything could go wrong, they wouldn't be sending me; you know that. They can send Sammy. Sammy doesn't have a wife. "Mary, you know I can't back out now. Nothing would ever be right with me again if I didn't go. "I've got to get started, Mary. "Phil, if you go, I won't be here when you get back—if you get back. I won't be here because I won't be the wife of a space pilot for the rest of my life. No matter how much I love you, I just couldn't take that, Phil. She finished and took another cigarette from the pack on the coffee table and put it to her lips. Phil stood watching her, the excitement completely gone from his eyes. "I wish you had told me this a long time ago, Mary," Phil said. "Yes, you did. I told you I could never be the wife of a space pilot. But I don't think I ever really believed it was possible—not until this morning when you said tonight was the take-off. "It isn't a dream.
output:  She thought she could protect herself if someone else went.
options:  She knows that Sammy is more careful, and would have a greater chance at mission success.  She thought she could protect herself if someone else went.  She thought that Sammy was more qualified.  She thought but his lack of family showed his dedication to his job.