$$A\overline B C\, + \,AB\overline C $$

$$ABC\, + \,A\overline B \overline C $$

$$\overline A BC\, + \,\overline A \overline B \overline C $$

$$\overline {AB} C\, + \,\overline A B\overline C $$

some but not all Boolean functions of 3 variables

all function of 3 variables but none of 4 variables

all functions of 3 variables and some but not all of 4 variables

all functions of 4 variablesand some but not all of 4 variables

2 input AND gates only.

2 number of 2-input XOR gates and 6 number of 2-input AND gates.

Two 2-input NOR gates and one XNOR gate.

XOR gates and shift registers.

0

1

$$\overline A B + A\overline B $$

$$\left( {\overline {A \oplus B} } \right) \oplus \left( {\overline {A \oplus B} } \right)$$