Question

A crime is committed during the hartal. There are four witnesses. The witnesses are logicians and make the following statements:
• Witness One says exactly one of the four witnesses is a liar.
• Witness Two says exactly two of the four witnesses are liars.
• Witness Three says exactly three of the four witnesses are liars.
• Witness Four says exactly four of the four witnesses are liars.
Assume that each of these statements is either true or false. How many of the witnesses are liars?

Answer 1

Three are liars

Answer 2

how?

Answer 3

Since there are four statements that ALL conflict each other. How many true statements can there be?
In other words, what is the maximum number of witnesses can be telling the truth?