We can have more arguments to prove that PQRS is a rhombus, but, the argument that we will use here is:
Let's look at the first statement, we have
![PT>QT](https://img.qammunity.org/2023/formulas/mathematics/college/59y9v5b3dnd0xaes7m4uxusgkdinf945g4.png)
That's not correct, it would just prove that QR/2 > PS/2,
![PR=QS](https://img.qammunity.org/2023/formulas/mathematics/college/nu2f5b9ph4bjw1mvdz11vnpt44pgk9ll5p.png)
This statement implies
![\begin{gathered} PR^2=QS^2 \\ \\ PS^2+SR^2=PQ^2+QR^2 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/ivdjzywvent8cs48my15b2dakoiteb5br6.png)
We cannot conclude that
![PS=SR=PQ=QR](https://img.qammunity.org/2023/formulas/mathematics/college/cm1y3tf8pgqqlf5wd532wkwr3ybrxgkklj.png)
The next statement is
![PT=QT](https://img.qammunity.org/2023/formulas/mathematics/college/uj01fvtfsslt8sbqs406gp4aaac844s932.png)
A rhombus can have different diagonals, and in fact they have. Then let's go to the next one
![ST=QT](https://img.qammunity.org/2023/formulas/mathematics/college/s0bf3815csw6f9cyyyrn6yy6hvqcwmc4x3.png)
That also not exactly says it's a rhombus, it's a pallelogram property.
![\angle SPT=\angle QPT](https://img.qammunity.org/2023/formulas/mathematics/college/su6gkmh2l6ftnrgo8uhmfi21alzpesuue9.png)
By doing that we have that the diagonal bissects the angle
That implies that the angle b is also bissect.
The last statment is
![\angle PTQ=\angle STR](https://img.qammunity.org/2023/formulas/mathematics/college/ec365jymcosz7s1r3fhf4huoeg2knnjuvj.png)
That's literally the vertex angle, it's true always, not only in that case, therefore the only possible answer is
![\angle SPT=\angle QPT](https://img.qammunity.org/2023/formulas/mathematics/college/su6gkmh2l6ftnrgo8uhmfi21alzpesuue9.png)
Pro