The word "imminent" means something that is about to happen very soon. However, in this sentence, the intended sense is that the event (his selection as leader) is not only about to happen soon but is also almost certain to happen — hence, "inevitable" (meaning unavoidable or certain to happen) is the closest in meaning in this context.

Let’s look at the options:

• Timely – means happening at the right time; not the same as imminent.
• Distant – the opposite of imminent.
• Unlikely – suggests doubt, which is opposite in tone.
• Inevitable – best fits the idea that something is bound to happen soon.

Thus, the most appropriate synonym for imminent in this context is inevitable.