Fill in the blank with the correct word from the options given:-

The painting's intricate details and subtle use of colors were ____ by the dim lighting in the gallery.

obscured

The correct answer is Option (2) → obscured

The sentence structure implies a negative effect of the "dim lighting" on the painting's qualities ("intricate details and subtle use of colors").

• Obscured means to keep from being seen; conceal or hide. Dim lighting would naturally hide the details and subtlety of a painting. 

• Enhanced → improved (incorrect)

• Amplified → increased (incorrect)

• Highlighted → made more noticeable (incorrect)