Answer:
A.

B.
Explanation:
Let V be the volume of full bottle of Jun's favorite hot sauce.
We have been given that Jun used x millimeters or 90% of his favorite bottle of hot sauce. This means that 90% of V equals to x millimeters.
We can represent this information in an equation as:

Upon multiplying both sides of our equation by 0.9 we will get,


Therefore, the expression
represents the volume of a full bottle of Jun's favorite hot sauce, in milliliters and option A is the correct choice.
Upon simplifying our expression we will get






Therefore, the expression
also represents the volume of a full bottle of Jun's favorite hot sauce, in milliliters and option B is the correct choice.