Struggling to come up with a solution to the following.

Im looking to create an IF formula for the following situation.

If another worksheet has the same value as the current worksheet then display the corresponing cell value of the other worksheet that lies in that row. The range of data to look up is say the whole of column C and then the output consists of the matching results in column A.

So there is a lot of data in each rows and need to output all of the matching entries.

Is this possible, any help would be most appreciated.