When the input is -2 ,the output is 4 which statement about this function must be true a. an input of -2 has infinitely many possible outputs b. an input of -2 has exactly one possible output c. an output of 4 has infinitely many inputs d. an output of 4 has exactly one input

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.