To solve this logical reasoning puzzle, we need to analyze the given statements carefully to determine who plays all three sports: badminton, swimming, and volleyball.

1. From the information provided:
   • Giri and Vani play badminton.
   • Jeeva and Shalu do not play badminton.
   • Shalu and Tanu are swimmers.
   • Jeeva, Vani, Shalu, and Tanu play volleyball.
   • Two among Jeeva, Vani, Shalu, and Tanu also play badminton (we already know Vani plays badminton).
2. Firstly, identify the person playing all three sports. The possible candidates are those who:
   • Play volleyball.
   • Play swimming (Shalu and Tanu).
   • Play badminton (Giri or Vani as starters; Tanu is revealed after). According to the information, Vani plays badminton, so our focus is on Tanu.
3. Analyzing the data:
   • Giri plays only badminton; he's not participating in volleyball or swimming.
   • Vani plays badminton and volleyball; no mention of swimming.
   • Jeeva plays volleyball but not badminton; no mention of swimming, so not ideal.
   • Shalu swims and plays volleyball but does not play badminton.
   • Tanu swims and plays volleyball. Since we know Vani plays badminton and there's another person who does too, Tanu must be the other person who plays all three sports.
4. Based on the deduction, Tanu is the one who plays all three sports: badminton, swimming, and volleyball.

Conclusion: Therefore, the person who plays all three sports is Tanu.