Four sentences are given below as A, B, C and D. Choose the sentence that is grammatically incorrect in describing the Trump administration effort to crack down on sanctuary cities.

Introduction / Context:
This question deals with political reporting language about the Trump administration and sanctuary cities. The aim is to identify incorrect usage of verbs and prepositions in formal English. Such structures are common in news articles and opinion pieces, making this type of question important for competitive exams that test advanced reading and grammar skills.

Given Data / Assumptions:
All four sentences discuss efforts to crack down on sanctuary cities.
Sanctuary cities are those that do not fully cooperate with federal immigration authorities.
Three options are intended to be grammatically acceptable, and one is incorrect.
You are required to pick the grammatically incorrect sentence.
Assume a formal journalistic or analytical tone is required.

Concept / Approach:
The key grammar point here is the correct use of the verb comply and the pattern comply with. The preposition with is fixed in this usage. The question also tests the correct structure of passive sentences and the acceptable use of phrasal verbs such as crack down on. Your approach should be to check phrasal verbs, passive constructions, and the object of comply.

Step-by-Step Solution:
Step 1: Look at option A. It uses is intensifying its efforts to crack down on so called sanctuary cities that refuse to comply with federal immigration authorities. The phrasal verb crack down on and the phrase comply with are both correct. Step 2: Option B states Efforts were intensified by the Trump administration to crack down on sanctuary cities that refused to comply with federal immigration authorities. This is a correct passive sentence and uses comply with. Step 3: Option C reads The so called sanctuary cities that refused to abide by federal immigration authorities were to be cracked down on by the intensified efforts of the Trump administration. Though slightly heavy, it is structurally acceptable and uses cracked down on correctly. Step 4: Option D says Federal immigration authorities must be complied into by sanctuary cities if the efforts of the Trump administration must be intensified. Step 5: The verb comply never takes into as a preposition. The standard pattern is comply with a law, rule, or authority. The phrase complied into is ungrammatical. Step 6: Therefore, option D is the grammatically incorrect sentence that must be selected.

Verification / Alternative check:
To verify, mentally correct option D. If you change it to Federal immigration authorities must be complied with by sanctuary cities, it becomes acceptable, confirming that the original version with complied into is wrong. This quick substitution technique helps confirm that the error lies in the choice of preposition, not in the overall idea.

Why Other Options Are Wrong:
Option A is acceptable because crack down on and comply with are both correct in political reporting language.
Option B is acceptable because the passive construction Efforts were intensified by is grammatically sound and clear.
Option C is acceptable though wordy, because cracked down on and abide by are standard expressions and the sentence has correct structure.
Option D misuses complied into, which is not an accepted pattern, so it is the incorrect sentence.

Common Pitfalls:
Students often overlook small prepositions in long political sentences and focus only on big nouns like administration or authorities. Another common mistake is assuming that all passive forms are awkward or wrong; in fact, the exam often focuses on subtle verb pattern errors rather than the mere presence of passive voice.

Final Answer:
The grammatically incorrect sentence is Option D. Federal immigration authorities must be complied into by sanctuary cities if the efforts of the Trump administration must be intensified.