What type of ukulele strings should I get?

I am planning on getting a Lanikai LU-21 Soprano Ukulele. I don't know what type of strings I should get with them. I was planning on getting Nylgut aquila strings, but I can't figure out what to get. Should I get http://www.amazon.com/Aquila-Premium-Ukulele-Strings-Soprano/dp/B003NJF1G8? Or are these not nylgut? Or should I get http://www.amazon.com/AQUILA-Ukulele-Strings-Regular-10U/dp/B001KY2LKC/ref=sr_1_2?s=musical-instruments&ie=UTF8&qid=1309313721&sr=1-2? But I dont know if these are for a soprano ukulele. Also does one pack come with four strings? If anyone knows anywhere else to buy these strings if these don't work please tell me.