I am pretty sure he answered it - he stated No you cannot sell your DLC, as in if you attempt to sell your account with your DLC associated with it you are violating the TOS for Origin and can have legal action taken against you. Technically, no one can stop you from giving your Origin Login information to someone else and receiving some form of monetary reimbursement for it, however if you choose to do this then there are possible legal consequences to this.
Also - you cannot sell just DLC as this is directly attached to your specific Origin account and there is no way to seperate the DLC from your account. I don't think any company is allowing you to sell digital downloads of games (even full retail versions) yet - this is one of the arguments people have for the price of digital downloads vs disc based games - a lot of people think that the cost of digital downloads should be markedly less than the price of disc based games since there is no manufacture cost or transportation cost that is normally a part of disc based games. So far there has been very little headway made in this regard - although Microsoft has reportedly stated that they will be looking into lowering the cost of digital downloads in the near future.
