Too much socializing in the workplace can C. keep you from reaching your performance goals. The questions clearly says 'too much,' which implies something negative, which means that B and D are not correct. A could be correct, but that's not really an important option, which is why I'd say it is incorrect. C is correct - if you socialize with people too much, spend time with them, have fun, you won't have the time to focus on your job and thus your performance will deteriorate.
