Which sign is installed immediately before the intersection of roadways?

Explanation

Sign 3.18.1 "No right turn" applies to the intersection of roadways in front of which it is placed, so it stands right before that intersection. Warning signs 1.6, 1.9 and 1.10, by contrast, are placed in advance: 50–100 m before the dangerous section in built-up areas and 150–300 m outside them (Rules, signs 3.18.1 and 1.5–1.33).