I added a image with the complete question as well as its choices.
Answer:
The rate of formation of X is 4 times the rate of disappearance of B
Explanation:
The given is:
3A + B .............> 4X + 2Y
From this, we can see that the ratio between the reactant B and the product X is 1 :4.
This means that for every reacting mole B, 4 moles of product X are formed, which means that the ratio between the disappearance of B and the formation of X is 1:4
Hope this helps :)
