There are four classes in grade six, 82 students in class one and class two, 84 students in class two and class three, 86 students in class three and class four, and () a: 82 students in class four and class one, B: 84 students in class one, C: 86 students in class two and class three, D: 88 students in class four and class one

There are four classes in grade six, 82 students in class one and class two, 84 students in class two and class three, 86 students in class three and class four, and () a: 82 students in class four and class one, B: 84 students in class one, C: 86 students in class two and class three, D: 88 students in class four and class one

There are 82 people in class 1 and class 2, and 86 people in class 3 and class 4, so the total number of people in the four classes is 168, because there are 84 people in class 2 and class 3, and the number of people in class 4 and class 1 is 168-84 = 84