Which similarity statement is true?
δsrq ~ δtrs
δsrq ~ δrtq
δsrq ~ δrts
δsrq ~ δqrt

ΔSRQ~ΔRTQ

Since ∠R and ∠T are both right angles, they must correspond in the similarity statement.  In the larger triangle, SQ is the hypotenuse; in the smaller triangle, RQ is the hypotenuse.  This means that SQ and RQ must correspond in the similarity statement.  This makes the 3rd one the best option.