3 . Which of these is an 8 bit register ? ( a) DX (b)CX (c)BX (d)AH 1 8. Which of these IC‘s is a 3 to 8 decoder used for decoding memory addresses ( a) 74LS245/8286 (b)8284A (c)74LS138 (d)74LS373 2 . One of these is an index register ( a) BP (b)SI (c)DX (d)IP 1 4. Which of these instructions writes a byte to memory ( a) MOVSB ( b ) LOD SB ( c ) SCA SB ( d ) STO SB 1 7. Which of these signals are bidirectional ( a) HOLD,HLDA (b)S1,s2 (c)RQ,GT (d)S0,S1