The following sentence has been split into four segments. Identify the segment that contains a grammatical error.

It can/get extreme cold/during/the winters.

The correct answer is get extreme cold.

Step-by-step Explanation:

1. Analyze the sentence structure:
The given sentence is: "It can get extreme cold during the winters."
Let's break down the sentence into its constituent grammatical parts:
- "It can" (subject + modal verb)
- "get" (base form verb following the modal verb "can")
- "extreme cold" (adjective/adverb modifier + predicate adjective)
- "during the winters" (prepositional phrase acting as an adverbial of time)

2. Identify the grammatical error:
In the segment "get extreme cold", the word "cold" functions as an adjective describing the weather state.
To modify an adjective like "cold", we must use an adverb rather than another adjective.
- "Extreme" is an adjective.
- "Extremely" is the corresponding adverb.

3. Formulate the correction:
Using the adjective "extreme" to modify the adjective "cold" is grammatically incorrect. It must be replaced by the adverb "extremely".
Therefore, the correct form of the segment is "get extremely cold".