We have flown several times with an infant in C and are (painfully) familiar with acceptable seats for infant.

Bottom line is there are no basinets positions in the C cabin (crazy I know).

Only the front row seats (not just the centre pair) are designated seats for travel with an infant. You will not be allowed to travel with an infant in any other seat in the C-cabin. It seems the other seats have some airbag feature which is not installed in the first row.

It is possible to assign other seats by phone but you will be moved at the airport. This caused us quite a bit of stress on our first trip in C with a 11 month old as we had pre-assigned a window and aisle pair but not in the first row - there was a bit of scramble to juggle seat assignments after we boarded.

Since then I have been careful to only assign first row seats but I have seen others travelling with infants having to play muscial chairs at the last mintue once on board.

To be perfectly honest, on a night flight from the East coast it's a bit of waste flying C with an infant. You are more likely to get some rest in a Y basinet position that in the front row of a full C cabin holding onto to baby all night.