Step 1: Read the sentence carefully
The sentence is: “My main reason for learning pharmacy was that my brother was one.”
At first glance, it looks grammatically correct, but when we analyze the pronoun "one," we see a problem.
Step 2: Identify the faulty reference
The pronoun "one" here is meant to refer back to a noun previously mentioned. However, the noun given is "pharmacy," which is the name of a subject or field of study, not a profession. Saying "my brother was one" creates a faulty reference because the reader expects "one" to stand for a profession like "pharmacist," not for the abstract field "pharmacy."
Step 3: Why this is incorrect
- "Pharmacy" = the study or science of preparing and dispensing drugs.
- "Pharmacist" = a person who practices pharmacy.
The writer’s intention is to say that the brother was a pharmacist. But by using "one" after "pharmacy," the pronoun has no logical or grammatical antecedent. This is why it is called a faulty reference by pronoun.
Step 4: Correction of the sentence
The corrected version should be: “My main reason for learning pharmacy was that my brother was a pharmacist.”
Here, the word "pharmacist" properly refers to the person and eliminates the pronoun error.
Final Answer: The correct option is (C) faulty reference by pronoun, because the pronoun "one" does not have a clear or logical antecedent in the sentence.