Conjunctive adverbs connect one clause to another clause, or one idea to another idea:
Joanne was very good at math; however, she is not good at English.
Descriptive adjectives can be separated with commas in a sentence such as:
Joanne did not want to pet the smelly, wet dog.
If you read each of these, or speak them, there is only one that suits the sentence correctly.
Go with the third one. Couldn't seems to fit pretty well there.
Answer:
Because she made the mess to begin with.
Explanation:
After the fire happened he scolded her because she had everything to do with it and it was almost a scold of relief.