Explanation: MOV instruction copies a word or byte from a specified source to a specified destination. The destination can be a register or a memory location. The source can be a register or a memory location or an immediate number .
For MOV CX 037AH: put immediate number 037AH to CX
For MOV BL, (437AH) : copy byte in Ds at offset 437AH to BL
For MOV AX BX : copy content register BX to AX
For MOV DL, (BX) : copy byte from memory at(BX) to DL
That identifies the differences. Good luck.