select all that apply semantics

In Introduction-to-Regression-with-R.Rmd, quiz 2 states 'select all that apply'. However, you can't select more than 1 option for these questions.

https://github.com/coding-for-reproducible-research/cfrrRtutorials/blob/b83cec6b8fc757b11ff4a0db2bdc18b99dfcff2c/inst/tutorials/Introduction%20to%20Regression%20with%20R/Introduction-to-Regression-with-R.Rmd#L390-L401

Technically this is fine. You can indeed 'select all that apply' as there is only one answer. However, this wording still confused some participants (as you might think both or neither option is correct).