美国的visa number在签证的哪个位置？

我现在在美国留学，正准备签证西班牙。application上有个问题是：
If you reside in a country other than your country of origin, have you permission to return to that country?: No
Yes (number and validity)..................................................................
Non-US Citizens residing in the U.S. Circle the applicable and provide Green Card or Visa number and validity (expiration date of your visa).
这个visa number在哪个位置哦?
是control number吗？