Survey Plugin Options

Hi
Can people recommend a plugin for user surveys, paid or otherwise? Specifically I need one that will allow a question split into two parts with a text answer + a yes/no answer:
Question 1a:
Do you think pigs are nice?
Ans:__________________
Question 1b: Can pigs fly?
yes/no

When collating the info in the admin 1b must be connected to 1a, but also sortable on it’s own

Thanks in advance