The mass of an object will be same as the total sum of its parts or pieces.
For example :
The mass of a whole pizza is 500 grams, If you divide it into half.
The mass of each half pizza will be 250 grams each.
The total mass of two half pizzas is 250 + 250 = 500 grams which is the same as the mass of the whole pizza.
So the correct answer is :
The total mass of all the pieces together will be "Equal to the original mass of the object".