General exam question G9A08

WhyIf a matching network at the transmitter end is adjusted to present a 1:1 SWR while the feed line's own SWR is 5:1, the resulting SWR on the feed line remains 5:1. A matching network at the transmitter end only changes what impedance the transmitter itself sees looking into the network, it can't reach back down the line and change the physical mismatch that already exists between the feed line and the antenna, so the SWR out on the feed line itself stays exactly what it was before, 5:1, answer B. The network fixing SWR at the transmitter (1:1) doesn't propagate down the line to fix the antenna-end mismatch, so A, C, and D are all wrong, the line's own SWR is unaffected by anything done at the transmitter end.