Directions: Rearrange the given sentences in a logical sequence to form a coherent paragraph, then answer the question below.

(A) He found that a high percentage of patients experienced functional loss before age 50.
(B) Recently, medical researchers identified a cellular protein linked to aggressive forms of Parkinson's.
(C) Parkinson’s is a progressive neurological disorder that gradually disrupts movement and motor control.
(D) Prompted by this discovery, Dr. Vance analyzed patient records from 40 major hospitals.
(E) These findings underscore the critical need for early diagnostic tools and targeted interventions.
(F) This ongoing physical decline is compounded by the reality that current medications merely address symptoms.

Which of the following should be the FIRST sentence after rearrangement?

The correct answer is C.

To find the correct logical sequence of the sentences, let us analyze each sentence step-by-step:

1. Sentence (C) introduces the main topic of the passage ("Parkinson’s is a progressive neurological disorder that gradually disrupts movement and motor control."). Since it is a standalone introductory statement establishing the topic, it serves as the opening sentence.
2. Sentence (F) refers to "This ongoing physical decline", directly connecting to the disruption of movement and motor control described in sentence (C).
3. Sentence (B) introduces a recent medical discovery regarding a cellular protein linked to aggressive forms of Parkinson's.
4. Sentence (D) begins with "Prompted by this discovery", which directly references the research discovery introduced in sentence (B).
5. Sentence (A) outlines the results of Dr. Vance's patient record analysis mentioned in sentence (D) ("He found that...").
6. Sentence (E) summarizes the broader implications of "These findings" described in sentence (A), serving as a logical conclusion.

Thus, the complete logical order of the paragraph is C – F – B – D – A – E.

Therefore, the FIRST sentence after rearrangement is (C).