[Q]: How does the sentence end?

Eric incoporated whole grains and vegetables into their diet but Dennis did not, so 

[A]: Dennis was much less healthy.


[Q]: How does the sentence end?

Elena didn't have a headache after using the paint but Lindsey did because 

[A]: Lindsey didn't use  a face mask.


[Q]: How does the sentence end?

Natalie went to see a patient in the hospital but not Betty because 

[A]:
Natalie was in town.