During my last cancelled KLM flight to which I had a train segment attached, I was wondering how exactly the EU261 needs to be interpreted with respect to the train segment.

Following flights:

DXB AMS departure 0155 - arrival 0615
AMS ZYR departure 0833 - arrival 1008

The DXB AMS flight was cancelled and I got rebooked on following EK flight:

DXB BRU departure 0810 - arrival 1240
I reached ZYR around 1430

Since the flight was cancelled and I arrived more than 2 hours late, I am entitled to a compensation.

Now the question is, how is the delay calculated?

A. train segment does not count, so 1240 - 0615 = 6h25 delay = 600 EUR compensation
B. train segment counts, scheduled ZYR arrival compares to BRU airport arrival, so 1240 - 1008 = 2h32 delay = 300 EUR compensation
C. train segment counts, scheduled ZYR arrival compares to my ZYR arrival, so 1430 - 1008 = 4h22 delay = 600 EUR compensation

I know that EU261 does not apply to train segments, but I do not know whether this means you can not claim anything if your train segment is late/cancelled, or this also means the train segment should not be taken into account at all when it comes to arrival time and delays.