In the forest food web shown below, which of the following organisms could be considered primary consumers?
hawk, fungi, bacteria
mouse, snake, bacteria
snake, mouse, hawk
insects, bird, mouse

Iwill you understand the question, rather than give you the answer, since you may have to do research.

a primary consumer is whatever comes next in a food chain or web after a producer (a.k.a a plant).   this means a primary consumer is either a herbivore or an omnivore.

some consumers (a.k.a animals), can be more than just a primary consumer, if they are omnivores.   this is because they eat plants and other animals.  

you will have to figure out which of the animals on your list are herbivores/omnivores and write them down as primary consumers.   be sure to note that the omnivores have are more than just primary consumers.

also decomposers are not primary consumers (bacteria or fungi), they break down organic matter and return it to the soil.

the reason i did not give you the answer directly is because understanding the question and being able to solve it yourself, as far more effective.

i hope this !

The answer is observations and interpreting.