Story needs to be completed:
Justin was a natural optimist but not Neil. 
OPTIONS:
- Justin found expressing gratitude came easily.
- Neil found expressing gratitude came easily.

My choice:
Justin found expressing gratitude came easily.
Problem: Continue the following story.

Craig but not Aaron had to wear a cast because 
OPTIONS:
- Craig had a bruise that was healing.
- Aaron had a bruise that was healing.
Here's how I want to continue it: Craig had a bruise that was healing.
Problem: Donald was more athletic than Kyle so 
OPTIONS:
- Donald handled the other easily in the tug-o-war.
- Kyle handled the other easily in the tug-o-war.

My choice: Donald handled the other easily in the tug-o-war.
[Q]: How does the sentence end?

Dennis showed Samuel his 100% grade on the geography exam last week.  
OPTIONS:
- Dennis was smart.
- Samuel was smart.

[A]: Dennis was smart.
QUES: Continue writing.

James preferred to take a bunch of pen with him for ease of carrying them other than pencil. The 

OPTIONS:
- pen is light.
- pencil is light.
+++++++++
ANS: pen is light.
QUES: Continue writing.

Kevin had become the victim of mail theft several times but Hunter never did because 

OPTIONS:
- Kevin did not have a secure mailbox.
- Hunter did not have a secure mailbox.
+++++++++
ANS:
Kevin did not have a secure mailbox.