Select the most appropriate option that can substitute the underlined word in the given sentence.
The culprit had been shot from the back by the police inspector.

The correct option to substitute the underlined word is "in".

Explanation and Logical Reasoning:

In English grammar, prepositions of place and body orientation are used specifically when describing where a person or body part receives an impact, injury, or action.

When someone is shot or struck in a specific part of the body (e.g., the back, the leg, the head), the correct preposition to express location on or inside the body is "in" (e.g., "shot in the back", "hit in the arm").

Let's analyze why the other options are incorrect:

1. from: "From" indicates origin or source (e.g., "shot from a distance" or "shot from behind"), but when directly referencing the body part hit, "from the back" is idiomatically incorrect in this context.

2. to: "To" indicates direction or movement towards a target, not the location of an impact on the body.

3. off: "Off" implies removal or distance from a surface, which does not fit the context of an injury or gunshot location.

Therefore, substituting "from" with "in" gives the grammatically correct sentence:
"The culprit had been shot in the back by the police inspector."