Consider the output A and B with $$I_{0},I_{1},I_{2}$$ and $$I_{3}$$ as input
$$A=\overline{I_{3}} \overline{I_{2}} I_{1}+I_{3}$$
$$B=\overline{I_{3}} I_{1}+I_{3}$$
The above circuit is

A

4:1 Multiplexer

B

De-Multiplexer

C

BCD circuit

D

Priority Encoder