Answer: The correct option is D, i.e., 15 units.
Explanation:
It is given that the length of segment TR can be represented by 5x-4.
From figure it is noticed that the side TR and RV is equal and the length of segment RV is 2x+5. So,



The value of x is 3, so the length of side RV is,

In triangle TRS and angle VRS,
TR=VR

RS=RS (common side)
By SAS rule of congruence triangle,

Therefore the side TS and VS are congruent sides.
From figure it is noticed that the length of side TS is 6x-3, therefore the length of side VS is also 6x-3.

Hence, the length of side VS is 15 units and option D is correct.