[Feature request] Choose exactly one out of several options

[clara-lupa]

It would be great to be able to create a poll where participants can choose exactly one out of several options, e.g.
"What is your favorite programming language? [ ] Java [ ] Ruby [x] Python [ ] C"
where I cannot choose more than one options. I ve been looking all over the web to find a tool like that, which is open source and privacy friendly, without any success.
thanks!
clara