Question

this sign is used to warn drivers about: upcoming intersections road construction road curves ahead changes in traffic lanes

Explanation:

The sign in the image is a standard road - curve warning sign. It is used to alert drivers that the road ahead will curve. Intersection signs usually have symbols related to cross - roads (like a plus sign or arrows indicating crossing paths). Road construction signs typically have symbols like a shovel, cones, or the word "Construction". Signs for changes in traffic lanes usually have arrows indicating lane shifts. Since the sign in the image has a curved arrow, it is for warning about road curves ahead.

Answer:

Road curves ahead