Fill in the blanks.
Although some schools _________ with the suggestion to introduce uniforms, many felt this was too extreme of a measure and began to _________ school dress codes.
The given parts of the sentence hint at how some schools embraced uniforms while others found a way around them, hence the verb 'complied: acted in accordance with a wish or command’ and the verb 'implement: put (a decision, plan, agreement, etc.) into effect’ should be used.
The meanings of the rest of the words are:
Flippant: not showing a serious or respectful attitude
Hiatus: a pause or break in continuity in a sequence or activity
Materialize: become actual fact; happen
Keen: having or showing eagerness or enthusiasm
Proposition: a statement or assertion that expresses a judgement or opinion
Delectable: delicious
Hence the correct answer is option 3.