Which One of These Samples Contains the Smallest Number of Molecules

Which one of these samples contains the smallest number of molecules?

A) 1.0 L of H₂ at STP (0 ^$\circ$ C and 1 atm)
B) 1.0 L of N₂ at STP
C) 1.0 L of H₂ at 20 ^$\circ$ C and 760 torr
D) 1.0 L of N₂ at 0 ^$\circ$ C and 800 torr
E) 1.0 L of He at STP