Option C: 'Supposed to' means 'to have to', 'a duty or responsibility'. It is relevant to the given sentence. 'It was the train's responsibility to arrive at 11:30, but it was an hour late.'
Hence option C is correct.
Option A: 'Made' in 'was made to' means that someone forcefully makes someone perform an action. 'Was made to' generally refers to people, and the meaning itself is not relevant here: a train can't be forced to arrive.
Option B: 'Planned' means 'to decide and make arrangements in advance'. It refers to a program or an event that needs to be organised. It does not refer to a train's arrival.
Option D: 'Hypothesized' refers to an unreal situation, or putting a hypothesis forward (a theory) without any factual evidence.
It relates to the given sentence and hence options A, B and D are wrong.