An experiment on the phonemic restoration effect would most likely include:

a) two similar-sounding letters (e. g., "t" and "c").
b) a categorical perception task.
c) a garden-path sentence.
d) an extraneous cough.

an extraneous cough.

Explanation:

Let us say you are in a stage delivering a speech and all of a suddenly in the middle of a speech,some of the sound in your sentence is replaced by an extraneous sound(extraneous mean not in anyway relevant to the speech that your delivering such as a cough or sound). The audience or listeners though are able to figure out the missing sound based on what you had said previously in your sentence and what followed just after that extraneous sound. This effect is referred to as a phonemic restoration.

In an experiment of phonemic restoration effect an experimenter will intentional remove a particular letter then read the sentence without that letter and then see what will audience say when they are asked what they hear and only to find that the audience or listeners just heard the sentence without even taking the note that there is a missing sound because they figure it out based on the prior context of the sentence or speech.

the best answer is b.

hope this : )