Consider the following graphs.

a

Which of these graphs is a tree?

A

B

C

A

B

C

b

Why is the following graph not a tree?

It is disconnected.

A

It has a loop.

B

It has multiple edges connecting the same vertices.

C

it has a circuit.

D

It is disconnected.

A

It has a loop.

B

It has multiple edges connecting the same vertices.

C

it has a circuit.

D

c

Why is the following graph not a tree?

It has a loop.

A

It is disconnected.

B

It has a circuit.

C

It has multiple edges connecting the same vertices.

D

It has a loop.

A

It is disconnected.

B

It has a circuit.

C

It has multiple edges connecting the same vertices.

D

Easy

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