Question

Chapter :- Progressions......
In the question above the correct answer given in my guide is option C but I did not understand how the answer is option C....

Answer 1

T(n+1) = 4n +5
T(n+1-1) = 4(n-1)+5 
T(n)=4n-4+5
T(n)=4n+1

Answer 2

put the value of tn as 4n+1 then u will get the answer