There are a lot of ifs and buts on this. Based on your age and salary and assuming the deductible is 1x state pension, the DC should be more beneficial to you, based on the current assumptions for projections, but as the previous poster says you will take all the risk on the investment side, whereas with DB the employer takes the risk.
You will be paying much less in employee conts for the DB, so if you decide to go that route then the extra shoudl be set aside as an AVC.
What is the deductable on the DB scheme? Is it one times state pension or 1.5 times state pension?
Is this a current DB scheme or a brand new one. If it is a current one, what is the current funding level? And how secure is the employer?
DB may be seen as guaranteed, but the big problem is that if the employer goes belly up or winds up the scheme there is a chance you could be left with very little or nothing. Any pensions currently being paid would have first call on the money.
With DC, the pot of money is yours no matter what happens. Of course currently with markets at a low, the pot of money may be worth less than put in but pensions are a longterm investment, and you still have 38 years to go.
Also - is this a one-off choice you have, or can you join up at some stage in the future?