119. Copy Semantics-I

A function takes a Buffer by value:

void process(Buffer buf) {  // By value -- copy!
   buf.data[0] = 0xFF;
}

Buffer original(64);
original.data[0] = 0xAA;
process(original);
printf("0x%02X", original.data[0]);

Assuming a correct deep copy constructor, what does original.data[0] print?