The correct answer is: b- have never seen.
Here's why:
"The view was wonderful" is in the past simple tense, describing a past event.
We want to express that until this moment, the speaker had never experienced anything similar. This indicates a completed action in the past relevant to the present.
Therefore, we need the present perfect tense to combine the past experience with the present.
"Have never seen" is the correct present perfect tense form of the verb "to see" used in the negative to convey that the speaker never had this experience before.
While "had never seen" might seem grammatically correct at first glance, it belongs to the past perfect tense, which is used to talk about an action that happened before another past action. Since we're talking about something that happened up to the present, the present perfect tense is the better choice.