The skipper of the (A)/ boat guide the vessel (B)/ through the storm and made (C)/ it safely into the port (D)/.

The correct answer is Option B.

Let us read the full sentence carefully by joining all its parts:

"The skipper of the boat guide the vessel through the storm and made it safely into the port."

Step 1: Identify the subject and the verbs in the sentence.

The subject of the sentence is "The skipper" — a singular, third-person noun.

The sentence uses two verbs to describe what the skipper did:

1. "guide" (found in Part B)
2. "made" (found in Part C)

Step 2: Check the tense consistency.

The second verb, "made", is clearly in the simple past tense. This tells us that the entire sentence is narrating a completed past event — something the skipper did during a storm.

For grammatical correctness, both verbs must agree in tense. Since "made" is in the past tense, the other verb must also be in the past tense.

Step 3: Spot the error in Part B.

The verb "guide" in Part B is in the base/present form, which is incorrect here. It must be changed to its simple past form, "guided", to maintain tense consistency throughout the sentence.

Incorrect: ...boat guide the vessel...
Correct: ...boat guided the vessel...

Step 4: Verify the other parts for errors.

• Part A — "The skipper of the" → Correct. The use of the definite article "the" is appropriate.
• Part C — "through the storm and made" → Correct. "Made" is properly in the past tense.
• Part D — "it safely into the port" → Correct. The adverb "safely" and the phrase are grammatically sound.

Conclusion:

The error lies in Part B. The verb "guide" should be replaced with "guided" to match the past tense used throughout the sentence. The corrected sentence reads:

"The skipper of the boat guided the vessel through the storm and made it safely into the port."