Answer:The Principal of the school lived by one principle: always do your best
Explanation:
The sentence with the correct usage is the first which is
-----The Principal of the school lived by one principle: always do your best
Principal and Principle are two words which have same sounds but with different meanings, They are referred to as homophones.
Principal here means the a person in authority known as a leader heading in a school while Principle means a rule or law or doctrine by which individuals or a group hold unto and both words should not be wrongly used as it will cause a wrong interpretation.
Therefore, in Sentences 2, 3 and 4 The two words have been wrongly used leaving Sentence 1 as the answer.
