Just check each option and see what works.
I am sorry to say, you have made these rather difficult to read. Is it \(\displaystyle t_{n+1}\) or \(\displaystyle t_{n}+1\)?.
If you want \(\displaystyle t_{n+1}\), then type t_(n+1). If you want \(\displaystyle t_{n}+1\), then type t_n+1
But if you want to learn how I typed it in LaTeX, then click on 'quote' at the upper right corner of my post and see the code I typed to make it display that way.
Look at D. If that is \(\displaystyle t_{n+1}=(t_{n}+1)^{2}\), then check this one out.
The way it is written suggests \(\displaystyle t_{n+1}=(t_{n+1})^{2}\) or \(\displaystyle t_{n}+1=(t_{n}+1)^{2}\)
If it is indeed \(\displaystyle t_{n+1}=(t_{n}+1)^{2}\), then see if this one works...hint....hint
Let n=1, then we have \(\displaystyle t_{2}=(t_{1}+1)^{2}\rightarrow t_{2}=(1+1)^{2}=4\)
Let n=2, then we have \(\displaystyle t_{3}=(t_{2}+1)^{2}\rightarrow t_{3}=(4+1)^{2}=25\)
and so on. See the pattern?.
