Which of the following statements regarding ozone is not true?

Question

$\begin{array}{1 1}\text{Ozone is an allotrope of oxygen}\\\text{The ozone layer protects the earth's surface from an excessive concentration of harmful ultraviolet radiation}\\\text{The conversion of oxygen into ozone is an exothermic process}\\\text{Ozone is much more powerful oxidizing agent than molecular oxygen}\end{array}$