Question

I was very hungry. I had eaten an hour earlier

=> Although

Answer 1

I was very hungry. I had eaten an hour earlier

=> Although I had eaten an hour earlier, I was very hungry

Answer 2

I was very hungry. I had eaten an hour earlier

=> Although I had eaten an hour earlier,I was very hungry.

Answer 3

I was very hungry. I had eaten an hour earlier

=> Although I had eaten an hour earlier, I was very hungry.