grammar - non-essential/non-restrictive prepositional phrases

1:

• a: I entered the house, through the window, and saw a few dancing cats.


• b: I entered the house through the window and saw a few dancing cats.


• c: I entered the house through the window, and saw a few dancing cats.

Which is one is the most correct? Which one would you most likely see in a book teaching about grammar.

2:

• a: Which one would be considered the most correct, by rigorous standards?


• b: Which one would, by rigorous standards, be considered the most correct?


• c: Which one would be considered, by rigorous standards, the most correct?


• d: Which one would by rigorous standards be considered the most correct?


• e: Which one would be considered the most correct by rigorous standards?

Which one of those would you most likely see in a grammar book? Which is the most correct and formal sounding. If more than one are correct, just tell me.

I hope somebody can clear up my confusion.

Greetings :)