Answer:
The correct option is D.
Step-by-step explanation:
We have to find the expresses this statement: A quantity x is equal to the sum of the squares of a and b.
The square of a can be written as a² and the square of b can be written as b².
The sum of squares of a and b can be written as
Since the quantity x is equal to the sum of the squares of a and b, therefore
Therefore option D is correct.