I think Giri is correct but understanding how you have wired up the elements to your data set is key here.
I just connected to your site and registered with a test email address.
First of all I would also initialize all of the drop downs to No (0) So that the calculation results in a valid value.
When I tried to manually call $w(’ #dataset1 ').setFieldValue(‘answer’, 250); [I guessed at the answer key property]. I got a dataset write error. the error said the dataset was read only. If your dataset is not called dataset1 then perhaps I was trying to write to the wrong dataset. Anyway perhaps using dataset new(), setFieldValue() and save() after you double check the dataset access might work. Alternatively unhook the dataset and use wix-data.insert instead 