Which of the following statements is not correct?

Question

$\begin{array}{1 1}\text{Divalent tin or lead compounds are essentially ionic in nature while tetravalent are generally covalent}\\\text{Tin(II) compounds are invariably reducing agents}\\\text{Lead(II) compounds are more stable than Pb(IV) compounds}\\(C_2H_5)_2Pb\text{ acts as an antiknocking compound in petrol}\end{array}$