The correct choice is Option 3: 'Because they wanted to be able to make the grandmother's rolled omelet, which they loved since childhood, by themselves.' The first paragraph states: '私は子供の頃から祖母の作る卵焼きが大好きで、いつか自分で同じものを作れるようなりたいと思っていました' (I loved the tamagoyaki my grandmother made since I was a child, and wanted to be able to make the same thing myself someday). This matches Option 3 exactly. Option 1 is wrong because it was the grandmother who ran a diner, not the author's declared career path. Option 4 is not mentioned in the text.