Question

Which of the following is a word borrowed from the Spanish language and used in the English language? la medicina el poncho el balcón el sándwich

Answer 1

Which do you think?

Answer 2

And, you can always look them up. Like:
http://dictionary.reference.com/browse/sandwich

Scroll down a bit and it says this:
Origin:
1755–65; named after the fourth Earl of Sandwich (1718–92)

Do the same for the others and see if any say they are Spanish in origin.