Assertion (A) The highest oxidation state of osmium is +8.
Reason (R ) Osmium is a 5d-block element.

Options

A. Both A and Rare true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A.
C. A is true but R is false.
D. A is false and R is True

Answer

B

Explanation

The highest oxidation state of osmium (Os) is +8. It is due to its ability to expand octet by using its all 8 electrons.