A Question is given followed by two Statements I and II. Consider the Question and the Statements.

Question:

If the average marks in a class are 60, then what is the number of students in the class?

Statement-I:

The highest marks in the class are 70 and the lowest marks are 50.

Statement-II:

Exclusion of highest and lowest marks from the class does not change the average.

Which one of the following is correct in respect of the above Question and the Statements?

There are two Classes A and B having 25 and 30 students respectively. In Class-A the highest score is 21 and lowest score is 17. In Class-B the highest score is 30 and lowest score is 22. Four students are shifted from Class-A to Class-B.

Consider the following statements:

1. The average score of Class-B will definitely decrease.

2. The average score of Class-A will definitely increase.

Which of the above statements is/are correct?