The factors responsible for the rapid spreading of bread mould on slices of bread are: (i) presence of large number of spores in air (ii) presence of large number of thread-like branched hyphae (iii) presence of moisture and nutrients (iv) formation of round shaped sporangia (a) (i) and (iii) (b) (ii) and (iv) (c) (i) and (ii) (d) (iii) and (iv)