Explanation:
Is that a grade is a rating while class is countable a group,collection, category or set sharing characteristics or attributes 
 
        
                    
             
        
        
        
<span><span>A.   </span>B-cells
</span>
Which type of white blood cells is produced in the thymus and destroys the
cell membranes of bacteria are B-cells. These b-cells are also known and called as B
lymphocytes. Their function primarily is to create antibodies which combats
antigens such as bacteria. They are also responsible for immune regulatory
indications –cytokines. In contrast, T-cells are a type of white blood cells
that combat any substance from the inside or within the body.
        
             
        
        
        
Answer:
Food labels tell how much of which is in the food.
Explanation:
Like- 
Sugar
Carbs
Dairy
Grams
and many more.
Take a look at the picture to see.