The box set was an important because:
a. It supported a more realistic acting style
b. It was an advancement made possible by electric lighting
c. It was banned
d. It paved the way for the introduction of wing and shutter set design
e. It allowed for more realistic details

A. It supported a more realistic acting style

Explanation:

Box sets create the illusion of an interior room on the stage and are contrasted with earlier forms of sets which contained sliding flaps and gaps between set pieces.

In the play style of realism, the box set of the stage was a room with either a plain black backdrop or three walls. The fourth wall was invisible, separating the characters from the audience, and the ceiling was tilted down at the far end of the stage and up toward the audience. Doors slammed instead of swinging when being shut, as in reality.

Answer is A. It supported a more realistic acting style.

Refer below.

Explanation:

The box set was an important because:

It supported a more realistic acting style

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