Donna, a family therapist, is explaining to her friend Betty, a 40 year-old African American female and Vice President at a large bank, that Betty is having difficulty finding a mate due to the marriage squeeze. In simple terms, What Donna means is that .

There is an imbalance in the ratio of men who are eligible for marriage to women who are eligible for marriage    

Explanation:

Marriage squeeze: The term marriage squeeze is described as a demographic imbalance whereby the number of different "potential brides" is not considered as equal to the number of "potential grooms". When every individual doesn't get an opportunity to marry someone then a few people will be deliberately squeezed out from the "marriage market" and won't be able to get to marry.

As per the question, in simpler terms, what Donna means is that imbalance in the ratio of male and female occurred.

- "sack of constantinople, (april 1204). the diversion of the fourth crusade from the holy land to attack, capture, and pillage the byzantine city of constantinople divided and dissipated the efforts of the christians to maintain the war against the muslims. the fourth crusade was corrupted from its purpose early on."

- "the crusades were a series of religious wars undertaken by the latin church. the first crusade arose after a call to arms in 1095 sermons by pope urban ii. the first crusade unleashed a wave of impassioned, pious catholic fury, which was of constantinople, the capital of the christian-controlled byzantine empire."

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