Which one of the following is a slime mould?

Slime moulds are saprophytic protists. Their body moves along decaying twigs and leaves, engulfing organic material.
Under suitable conditions they form an aggregation called a plasmodium, which may grow and spread over several feet.
Physarum (for example Physarum polycephalum, the 'many-headed slime') is an acellular slime mould that lives in shady, cool, moist places such as decaying leaves and logs.
During unfavourable conditions the plasmodium differentiates and forms fruiting bodies bearing spores at their tips.
Thiobacillus is a chemoautotrophic sulphur bacterium.
Anabaena is a filamentous cyanobacterium (blue-green alga).
Rhizopus is the bread mould, a fungus of the class Phycomycetes.
So the slime mould is Physarum.