Complete the following sentence with commonly used familiar nouns:
He is so adamant that at times it is like talking to a __________ wall.
a) Stone
b) Brick
c) Wooden
d) Rock

Hint: The meaning of the word adamant means unshakable, impossible to persuade or change opinion. If you stubbornly refuse to change your mind about something you are adamant about it.

Complete answer:
The above statement is an idiomatic expression. An idiom or idiomatic expression is an expression, word or a phrase that has a figurative meaning. The meaning is quite different from the literal meaning. In other words, idioms don’t mean exactly what the words say. For example, when we say it is raining cats and dogs it means that it is raining heavily.
>Option A) STONE is incorrect as it does not form the required meaning in the sentence.
>Option B) BRICK is the correct answer. The complete idiomatic expression is – He is so adamant that at times it is like talking to a brick wall. This idiomatic expression is used for somebody who refuses to listen to you.
>Option C) WOODEN is incorrect as it does not form the required meaning in the sentence.
>Option D) ROCK is incorrect as it does not form the required meaning in the sentence.

  So, option C is the correct answer

Note: In such types of questions it is important to understand the meaning in which the sentence is written.