(A) greatly benefit brain function

(B) and help avoid the negative

(C) short afternoon naps can

(D) effects of prolonged sleep sessions

The following question gives a sentence which has been divided into four parts which may not be in their correct order of narrative. The sentence is then followed by five options, one of which gives the sequence of the rearranged parts to make the sentence meaningful. Choose the option which gives the correct sequence of the parts. If the sentence is already arranged in the correct sequence, mark option " No rearrangement required " as the answer.

The correct option is CABD.

To form a grammatically correct and meaningful sentence, let us analyze each of the given parts:

(A) greatly benefit brain function

(B) and help avoid the negative

(C) short afternoon naps can

(D) effects of prolonged sleep sessions

Step-by-step rearrangement:

1. Identify the subject/beginning of the sentence: Part (C) "short afternoon naps can" introduces the subject ("short afternoon naps") and the modal verb ("can"). This makes part (C) the best introductory segment of the sentence.

2. Connect the verb phrase to the modal verb: Part (A) "greatly benefit brain function" starts with the main verb phrase "greatly benefit" which naturally follows the modal verb "can" in part (C). Combining (C) and (A) gives: "short afternoon naps can greatly benefit brain function".

3. Add the conjunction and continuation: Part (B) "and help avoid the negative" joins the second predicate using the conjunction "and". This smoothly follows part (A): "short afternoon naps can greatly benefit brain function and help avoid the negative".

4. Complete the object of the preposition: Part (D) "effects of prolonged sleep sessions" completes the phrase "the negative effects...", specifying what is being avoided. Adding part (D) finishes the sentence logically and grammatically.

Combining these parts in order gives:

(C) short afternoon naps can (A) greatly benefit brain function (B) and help avoid the negative (D) effects of prolonged sleep sessions.

Thus, the correct sequence is CABD.