Which describes independent events?
a) selecting two tickets by choosing a raffle ticket at random from a jar and disposing of the first ticket before selecting the second ticket.
b) selecting a blue and green balloon by choosing one string at a time at random from a clown's hand, handing the first choice to your brother.
c) rolling two ones in a row using a standard die.
d) getting 5 multiple choice questions correct if you select at random from each of the possible answers, never repeating an answer choice.

C.

All of the other answers are dependent because once the first action is complete, the sample from which you are selecting the second item is different from the first...

for example, A,

If you draw the first ticket out of, say, 25 total tickets, there is a 1/25 chance you will get that ticket. If you dispose of it and then draw a second ticket, there are now 24 total tickets so there is a 1/24 chance of getting that ticket.

C is independent because the dice itself doesn't change when you roll it again... there is a 1/6 chance of getting a one each separate time you roll.

hope that helped!