有办法!

问：你们在美国的费用谁来承担？
答: 儿子和儿媳承担。
看了所有的证明，最后说：对不起，我不能给你们签证，你的儿子是学生，不能负担你们的费用。我不能保证你们会回来。

Sounds like that the Office rejected the visa because
he/she was questioning your ability to pay for
the cost of your parents.
1.Can you try to have your parent show the officer
their own financial evidence to cover the cost of the
travel and 3~6 month staying with you.

2. bring your father's 工作证明 .

Hope it will help.
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