AP EAMCET Engineering 18 Sep 2020 Shift 1 Paper

The oxidation number of an element in a compound is evaluated on the basis of certain rules. Which of the following rules is not correct?
A. The oxidation number of hydrogen is always +1
B. The algebraic sum of all the oxidation numbers of all elements in a compound is zero
C. An element in the free or the uncombined state bears oxidation number zero
D. In all its compounds, the Oxidation number of fluorine is −1