advise not to vs warn against

[vkhu]

Rewrite this sentence:

1. My friend told me, “If I were you, I would not smoke so much.”

A. My friend advised me not to smoke so much.
B. My friend warned me against smoking so much.

The key said A is the answer but I don't get why I couldn't use B. Some explanation please

[5jj]

Your friend was advising you not warning (meaning 1) you.

"If you don't stop smoking, you'll die soon." That's a warning.

[SoothingDave]

This seems like a poor question. Depending on context and tone, you could consider it a warning.

[emsr2d2]

In my opinion, she actually did neither. She simply stated a fact - that she would not smoke if she were me. If one has to be chosen, though, I would say it's advice rather than a warning.