What is the former sweethearts motive in a wedding gift

In the story "A Wedding Gift," we meet a bachelor who has decided that he wants to get married. However, he has had other lovers in the past. In particular, his current lover is still interested in him, but he pushes her aside in order to marry the woman he now loves. What he does not know is that the former sweetheart's motive is that she is carrying his child, and as she dies during childbirth, he is responsible for taking care of the baby.

the answer should be d) he was one of those young thousands who greeted the war with a certain amount of relief, welcoming the liberation from webs of tangled emotion" since it is the best option because it shows his desire to free himself. 

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