Answer:
Shrews
Step-by-step explanation:
I think Shrews because other animals are either frogs prey or the frog is the prey to rest. But frog and shrew can't eat eachother.
Frog's :- Shrew's :-
Hawks ------> Frog Hawk --------> Shrew
Snake -------> Frog Snake --------> Shrew
Frog --------->Cricket Shrew -------> Cricket
Shrew ----x---- Frog. Frog ----x---- Shrew
In simple way the Shrews are in competition with frog.
Hope this helps you
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