Problem: How does the sentence end?

Neil had weaker muscles than Samuel did,  because 
OPTIONS:
- Neil worked out at the gym with barbells.
- Samuel worked out at the gym with barbells.
Answer: Samuel worked out at the gym with barbells.

Problem: How does the sentence end?

I could install more programs on my PC than on my phone because there is less space on my 
OPTIONS:
- PC .
- phone .
Answer: phone .

Problem: How does the sentence end?

The janitor wanted to put the garbage in the bag but the 
OPTIONS:
- garbage  was too large.
- bag  was too large.
Answer: garbage  was too large.

Problem: How does the sentence end?

The man had many conflicts with Christine but not Cynthia because 
OPTIONS:
- Christine was a mean and grumpy person.
- Cynthia was a mean and grumpy person.
Answer:
Christine was a mean and grumpy person.