Step 1: Understanding the Concept:
This is a sentence rearrangement task. To solve this, we must identify the core structure of an English sentence: $Subject + Verb + Object + Modifiers$.
The goal is to create a sequence that is logical and follows standard syntactic rules.
Step 2: Detailed Explanation:
Let's analyze the fragments:
- P: "the scientist presented" $\rightarrow$ Contains the Subject (Scientist) and the Verb (presented). This is the "Anchor" of the sentence.
- Q: "at the international conference" $\rightarrow$ This is an Adverbial Phrase of Place.
- R: "his groundbreaking research" $\rightarrow$ This is the Direct Object. The verb "presented" requires an object (what was presented?).
- S: "confidently" $\rightarrow$ This is an Adverb of Manner.
1. Determining the Sequence:
- Step 1: Start with the Subject/Verb: P ("the scientist presented").
- Add the Direct Object: R ("his groundbreaking research"). In English, the object usually follows the verb directly.
- Step 2: Add the Adverb of Manner: S ("confidently"). Adverbs of manner typically follow the object.
- Step 3: Add the Adverbial of Place: Q ("at the international conference"). Phrases of place and time usually come at the very end.
2. Verification:
"The scientist (S) presented (V) his groundbreaking research (O) confidently (M) at the international conference (P)."
This follows the S-V-O-M-P (Subject-Verb-Object-Manner-Place) rule.
3. Why others are wrong:
- (A) P Q R S: Places the location between the verb and its object. This is unnatural in English.
- (C) P S R Q: "presented confidently his research." While understandable, placing the adverb before a long object is less standard than placing it after.
- (D) Q P R S: Starting with the location is possible but usually requires a comma ("At the conference, the scientist...") and is less direct than starting with the subject.
Step 3: Final Answer:
The most logical and grammatically standard sequence is P-R-S-Q. Therefore, Option (B) is correct.