The order of aciditic strength among the given phenols is :

Options

A. `III gt IV gt I gt II`
B. `I gt IV gt III gt II`
C. `II gt I gt III gt IV`
D. `IV gt III gt I gt II`

Explanation

Due to attachment of electrons withdrawing groups like the nitro group on phenol the acidic strength increases, while attachment of electron donating groups causes the acidic strength to decrease. In given compounds, p-nitrophenol is more acidic then m-nitrophenol because at para-position`-NO_(2)` group shows more -I and -R effect than ortho and meta-positions.
Hence, `IV gt III` ( acidic strength). In phenol and p-cresol, phenol in more acidic than p-cresol because`-CH_(3)` group is an electron donating group, hence decreases the acidic strength. Thus, order of acidic strength of therefore `IV gt III gt I gt II`