4. Which of the following instructions are valid or invalid? If valid, indicate which bit is altered (D0 to D7, DO is LSB and D7 is MSB). For example, if the 5th bit of ACC is altered, the answer should be D4 of ACC, which is ACC.4 For the 5th bit of PO (8 bits: PO.0 to PO.7), the answer should be 'PO.4, which is the 5th bit of PO a) SETB P1 b) CLR ACC.5 c) CLR 80H d) CLR 90H e) SETB B.4 (Back Side!!) 4. Which of the following instructions are valid or invalid? If valid, indicate which bit is altered (D0 to D7, DO is LSB and D7 is MSB). For example, if the 5th bit of ACC is altered, the answer should be D4 of ACC, which is ACC.4 For the 5th bit of PO (8 bits: PO.0 to PO.7), the answer should be 'PO.4, which is the 5th bit of PO a) SETB P1 b) CLR ACC.5 c) CLR 80H d) CLR 90H e) SETB B.4 (Back Side!!)