Most of you used your high level knowledge to make it work, but here it is for begineers like me who would like to solve it with an easy method:

import java.io.; import java.util.;

public class Solution {

public static void main(String[] args) {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int arrObj;

    // data list
    ArrayList<ArrayList<Integer>> dataList = new ArrayList<>();
    // making array list to store data
    for (int i = 0; i < n; i++){

        int nArray = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<>();
        for(int j = 0; j < nArray; j++){

            arrObj = sc.nextInt();

            arr.add(arrObj);

        }
        // System.out.println(arr);
        dataList.add(arr);
    }


    int n2 = sc.nextInt();
    //query list
    // ArrayList<ArrayList<Integer>> queryList = new ArrayList<>();
    // making data list to fetch data or else print Erorr
    for (int i = 0; i < n2; i++){

        int row = sc.nextInt();
        int coloumn = sc.nextInt();
        // System.out.println(arr2);
        try{
            System.out.println(dataList.get(row-1).get(coloumn-1));
        }
        catch(Exception e){
            System.out.println("ERROR!");
        }


    }


}

}

`