B

C

C

B

B

C

C

B

B

D

C

C

A

B

A

A

C

D

A

A

A

A

B

D

A

D

C

D

B

D

B

C

D

C

D

B

A

D

B

A

D

A

C

D

B

D

B

B

D

B

B

C

B

D