Okay if I am correct this is on probability, right?
So you basically have to put 5 over 12, 5/12 because five of the doen batteries are dead. Then, divide 5 over 12, and you'll get .416, and then divide 4 over 16, and you will get get 0.25 which reduces down to 1/4 which is your answer. So, your answer is (c) because the answer says the first four you pick will all work.
Hope this gives you a good deal of help! Rate as brainliest if it was the best answer. Thanks!