Phrasal verb

[GOODMANS]

Good morning. Please I need help choosing the correct phrasal verb in the list below:
[come on, come out, come off, come up]
Night will soon __________.

[darcy]

The answer is 'come on'. This phrasal verb can mean 'develop gradually'.
Examples:
I can feel a headache coming on.
How's your project coming on?

Here's one from a novel by Arthur Conan Doyle:
... he came to a mountain torrent which he was sure that he had never seen before. Convinced that he had taken the wrong turn, he tried another, but with the same result. Night was coming on rapidly, and it was almost dark before he at last found ...

[GOODMANS]

Thanks a lot for your answer.