Problem: How does the sentence end?

Katrina asked Angela to put the dishes into the dishwasher, so 
OPTIONS:
- Katrina could finish cooking.
- Angela could finish cooking.
Answer: Katrina could finish cooking.
sentence: Benjamin accused Adam of taking the last jar of peanut butter,  OPTIONS:
- Benjamin is a distrusting person.
- Adam is a distrusting person.
complete: Benjamin is a distrusting person.
Angela was diurnal while Erin was nocturnal so 
OPTIONS:
- Angela preferred to stay out late at night.
- Erin preferred to stay out late at night.
Erin preferred to stay out late at night.
Input: Continue writing.

Her hair grew better with the shampoo so we threw out the vitamin bottle as the 
OPTIONS:
- shampoo was aged.
- vitamin was aged.

Continued: vitamin was aged.
Story needs to be completed:
Justin started guitar lessons yesterday, whereas Donald had been playing for ten years, so 
OPTIONS:
- Justin was very clumsy in their playing.
- Donald was very clumsy in their playing.

My choice:
Justin was very clumsy in their playing.
Problem: How does the sentence end?

I prefer to use a spray rather than a trap to kill cockroaches as the 
OPTIONS:
- spray is slow and ineffective.
- trap is slow and ineffective.
Answer:
trap is slow and ineffective.