Explanation:
Below is an attachment containing the solution.
Because the core is a big ball of iron
For Ethernet, if an adapter determines that a frame it has just received is addressed to a different adapter
a. it discards the frame without sending an error message to the network layer
b. it sends a NACK (not acknowledged frame) to the sending host
c. it delivers the frame to the network layer, and lets the network layer decide what to do
d. it discards the frame and sends an error message to the network layer
Answer:
Option A
Explanation:
The nodal address has to match the signal message address for it to function well but if the it doesn't match the nodal receiver address, it disregards it.
I'm not sure about the rest but for question 2:
A theory is an attempt to come up with a big picture of all we know so far. It also drives future research as people do experiments to see if what the theory predicts actually happens. When experiments don’t support the theory, you have to change the theory and try again. That’s how science works. We come up with a “best guess” (theory), and then do research to test it’s accuracy. As we discover contradictions, we adjust the theory to take those into account, and then start testing the validity of the new theory.