What if inheritance occurs for a class with an embedded covergroup?

As the code shown below, what is the relationship between those two covergroup named cg?

  class A;
     int a;
     covergroup cg @(clk);
        option.per_instance = 1;
        v_a: coverpoint a
          iff(reset){}
     endgroup // cg
  endclass // A

   class B extends A;
     int b;
      
     covergroup cg @(clk);
        option.per_instance = 1;
        v_b: coverpoint b
          iff(reset){}
        
     endgroup // cg

   endclass // B