In Pokémon, Bulbasaur is the only starter pokemon that is a Grass/Poison type.

The answer is true because among the three original starter Pokémon in the Pokémon series (Bulbasaur, Squirtle, and Charmander), Bulbasaur is the only one that has a dual Grass/Poison type. Squirtle is a pure Water-type Pokémon, and Charmander is a pure Fire-type Pokémon. This unique typing gives Bulbasaur advantage over certain types of Pokémon while also making it weak against others, adding a layer of strategy to battles.