Answer:
The correct option is B) £2621440.
Step-by-step explanation:
Consider the provided information.
Contestants are asked a number of questions; they get £5 if they only answer one question correctly, £10 if they answer two questions correctly, £20 if they answer three questions correctly and so on.
This form a G.P
5, 10, 20, 40.....
The nth term of a GP series is 
Where a₁ is the first term and r is the common ratio.
Here the first term is 5 and we need to find the value of 20th term.
The common ratio is: 
Substitute the respective values in the above formula.




Hence, the correct option is B) £2621440.