The third diagram is the one that shows how much flour is needed.
Which diagram shows how much flour you need?
We know that you need (3/4) of a cup of flour for each batch of cookies. If you want to make 3 batches, then you need 3 times that amoung, which is:
3*(3/4) of a cup = (9/4) of a cup = (2 + 1/14) of a cup.
The diagram that shows this is the third diagram, so that is the correct option.