HINT:
Looking at the choices, you can see that they are A) 25% and B) 50% and C) 75%. This means you can round the approximate percentage according to the pie chart to around these numbers
So...
what do you think is the percentage of the pie chart that is orange for the US?
what do you think is the percentage of the pie chart that is orange for the UK?
Now subtract them and pick your choice!
The US seems about 65% and the UK about 15%.
Can you do it now?
You are very welcome!
:P