Yes. It is 3.
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3 it is.
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I am not sure I understand your question correctly. If there is a US citizen husband, who needs co-sponsor because he cannot sponsor his foreign wife, and the co-sponsor is single, it should be 2. However, if there is a married joint sponsor, who sponsors an immigrant, it is 3, or a single co-sponsor, who sponsors primary immigrant and her husband, it is 3.
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