Which of the following statements is true regarding family types and income in the United States in the decades since the 1970s? Group of answer choices There are more families with two high earners and more families with one low earner, resulting in a bigger income gap between richer and poorer families. There are fewer families with two high earners and more families with one low earner, resulting in an downward trend in average family income among all types of families. There are slightly more families with two low earners and slightly fewer families with one high earner, but the income gap between richer and poorer families has remained about the same. There are fewer families with two low earners and more families with two high earners, resulting in a smaller income gap between richer and poorer families