In the 1980 United States census, marital status was described under one of five categories: single, now married (but not separated), separated, divorced, widowed. In the category "separated," including both those who were legally separated and those who were estranged and living apart from their spouses, one million more women than men were counted.
Which of the following, if true, provide(s) or contribute(s) to an explanation for this result ？（）
Ⅰ. There are more women of marriageable, age than men of marriageable age in the United States.
Ⅱ. More of the separated men than separated women in the United States could not be found by the census takers during the census.
Ⅲ. Many more separated men than separated women left the United States for residence in another country.
A．Ⅰ only.
B．Ⅱ only.
C．Ⅲ only.
D．Ⅰ and Ⅱ only.
E．Ⅱ and Ⅲ only.