Need help with priority diagnoses

I need 3 diagnoses for this patient:

>60 yr old male

>morbid obesity (about 500 lbs)

>in hospital for abdominal pain, they did a cholecystectomy a month ago, he's still there because of "placement issues"

>current C. diff infection

>unable to perform ADLs, cannot get out of bed or even turn on his own

>hx of type 2 DM, bilateral knee replacement, depression (also was currently dx'd with depression)

>multiple skin issues d/t obesity skin folds & bed sores

>complains of abdominal pain (it's always a "7") but the nurses all say "he just likes his meds"

I've come up with:

- Diarrhea r/t infectious process

- Impaired Skin Integrity r/t immobilization and moisture

- Acute Pain r/t surgery

- Imbalanced nutrition (more than body requirements) r/t excessive intake & sedentary lifestyle

- Powerlessness r/t inability to perform self-care and control eating habits (AEB depression)

- Risk for infection r/t compromised skin integrity

I need to pick three that are most important, and put those in order. I'm stuck. I'm thinking it should be like this:

1. Diarrhea

2. Impaired Skin Integrity

3. Imbalanced nutrition

I have Diarrhea first because that's the most current "big issue", and probably the first thing that needs to be fixed, right? Then I'd need to address the skin issues and try to get him to do things on his own, get him moving around a bit more. But I don't know what's realistic for this guy. Also, he's been losing weight since being in the hospital, so not sure "imbalanced nutrition" is appropriate. Any help would greatly be appreciated.