Fill in the blank (_) in the following sentence from the following choices.
Sentence: After Matthew got knee surgery, Dennis helped them to get around, and _ was grateful to them for it.

Choice 1: After Matthew got knee surgery, Dennis helped them to get around, and Matthew was grateful to them for it.
Choice 2: After Matthew got knee surgery, Dennis helped them to get around, and Dennis was grateful to them for it.
Which of the choices is correct? Respond with only "1" or "2" and no additional text.
1
1.