1.10 Crash

Ever since the 1.10 update, when I go to play minecraft. I click on to a world/server and then it says there has been an error. I don't know how to fix this so could anyone please tell me how. Even when I switch my version to 1.9.4 or lower it keeps crashing. Is it because of 1.10?. Please, some one answer tell how to fix this. I haven't been able to play minecraft in 6 days not even offline