given that it is 16bit CPU ==> 16 bits at a time access.
Memory = 64K word = 16 bits required ===> one memory access can be sufficient to know the value in direct mode
Indirect means, it requires 2 Memory references.
Instruction size = 64 bits ===> 4 memory references required
So, memory references = Indirect + Direct + Direct = 2+1+1 = 4 ( without fetch )
memory references = Fetch + Indirect + Direct + Direct = 4+2+1+1 = 8 ( with fetch )
as per me, data means references of variables but not the code (i.e., not count the accessing instructions )