Q21,P2,J15. Consider the given graph.

1-2-> 28
2-3->16
3-4->12
4-5->22
5-6->25
6-1->10
2-7->14
7-4->18
7-5->24.

its minimum cost spanning tree is---------------------.

Answer B.
Explanation.

Kruskal algo arrange weights in ascending order.

6-1->10
3-4->12
2-7->14
2-3->16
7-4->18
4-5->22
7-5->24
5-6->25
1-2->28.
put all the nodes in ascending order so that it does not form a circuit.untill all the nodes are traversed.
so nodes are.
6-1,3-4,2-7,2-3,4-5,5-6,1-2. it avoids 7-4 and 7-5  to avoid the circuit.