Backdoor Roth and Basis Question

I’m setting up a backdoor Roth conversion in Turbo Tax.  When setting up the 1099-R, I’m at the section:

 

Let us know if you have any non-deductible contribution to your traditional IRA from prior years.

 

I’ve never made a non-deductible IRA contribution during prior years, but in 2016 I did rollover a
before tax 401-K to a traditional IRA. 

 

Does this 401-K rollover to traditional IRA apply to this basis question and if so how do I handle it?