[Q]: How does the sentence end?

Betty greatly embarrassed themselves in front of Christine. 
OPTIONS:
- Betty hence felt the need to apologise.
- Christine hence felt the need to apologise.

[A]: Betty hence felt the need to apologise.
QUES: Continue writing.

Laura was in critical condition and being helped by Elena because 

OPTIONS:
- Laura was an emergency doctor.
- Elena was an emergency doctor.
+++++++++
ANS: Elena was an emergency doctor.
Problem: How does the sentence end?

The kids liked to use crayons on the card instead of markers, because the 
OPTIONS:
- markers had more variety.
- crayons had more variety.
Answer: crayons had more variety.
sentence: The serum Betty was using doesn't work as well as Amy's because  OPTIONS:
- Betty shopped at a high end store.
- Amy shopped at a high end store.
complete: Amy shopped at a high end store.
The piercing was a lot less painful than the tattoo because the 
OPTIONS:
- piercing was a lot quicker.
- tattoo was a lot quicker.
piercing was a lot quicker.
Problem: Continue the following story.

Justin won the competition for growing the largest plant and beat Kenneth even though 
OPTIONS:
- Justin was known to have a green thumb.
- Kenneth was known to have a green thumb.
Here's how I want to continue it:
Kenneth was known to have a green thumb.