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I'd go with . It seems the safest, and also lets you keep a (faint) possibility of sanshokou.

Hmm. Look at some of considerations:
* Ittsu with the manzu tiles.
* 7-8-9 Sanshoku? Tough sell considering the three 9-sou dropped on the left.
* Pinfu, where I'd pair with the 9-wan, and work with the rest. It'd be nice if an 8-wan does come out along the way.

* South may not like manzu.
* Chun call by West, and no dropped sou tiles.
* North is likely shooting tanyao.

Drop:

No real value keeping another one of these in hand, especially when one is already dropped in own discard.

is the most useless tile here: we've already discarded it, there aren't any more of it on the board, so there's no difference between the 799-dot shape and a 79-dot shape. I certainly don't want to break up the pair of dora, nor do I want to break up the more potentially useful shapes in the rest of the hand. Even putting aside my plans for the rest of this hand, is gone.

Keeping the widest path to iishanten and pinfu. Neither sanshoku nor ittsuu is truly reachable, as most draws leading towards them also help the pinfu immensely, and on top of that the critical 8-man and 9-sou are rare. This will most likely be a pinfu dora 3 after we draw 8pin or a riichi dora3 waiting on that 8pin, but I'm not letting go of the 8man chance at this point. Both south and west are worth watching, but the high mans/pins aren't very dangerous against either, so no worries here.

If we still want to win, keeping the 9d pair means abandoning the 9c dora pair at some point. That isn't something we want to do both because we don't want to remove dora, and because the dora is surprisingly safe against everybody so we can defend with it later. Keeping the 1c allows it to connect with the [345]c if we happen to draw 2c. There's only four tiles left in that wait, but it would allow us to remove the [7-9]d middle wait which will prevent us from scoring pinfu unless we draw it beforehand (and I wouldn't want to reach here).

Also, I wouldn't be surprised if North is aiming for a nagashi mangan over there. There are still a bunch of tiles left that he can discard.