A plane truss is shown in the figure (not drawn to scale).

Which one of the options contains ONLY zero force members in the truss?

1. $\text{FG,FI,HI,RS}$
2. $\text{FG,FH,HI,RS}$
3. $\text{FI,HI,PR,RS}$
4. $\text{FI,FG,RS,PR}$