1 : A four-year study P : that babies feel more comfortable Q : conducted by the Infant Testing Centre R : around other babies S : clearly suggests 6 : than with strange adults. The Proper sequence should be:

The correct answer is A. PRSQ.

The first sentence is a complete sentence, so it must be the beginning of the paragraph. The second sentence is a subordinate clause, so it must follow the first sentence. The third sentence is a complete sentence, so it must follow the second sentence. The fourth sentence is a subordinate clause, so it must follow the third sentence. The fifth sentence is a complete sentence, so it must follow the fourth sentence. The sixth sentence is a subordinate clause, so it must follow the fifth sentence.

Therefore, the correct sequence is A. PRSQ.

Here is a more detailed explanation of each option:

• Option A: PRSQ. This is the correct answer. The first sentence is a complete sentence, so it must be the beginning of the paragraph. The second sentence is a subordinate clause, so it must follow the first sentence. The third sentence is a complete sentence, so it must follow the second sentence. The fourth sentence is a subordinate clause, so it must follow the third sentence. The fifth sentence is a complete sentence, so it must follow the fourth sentence. The sixth sentence is a subordinate clause, so it must follow the fifth sentence.
• Option B: QPRS. This is not the correct answer. The second sentence is a subordinate clause, so it cannot be the beginning of the paragraph. The first sentence is a complete sentence, so it must be the beginning of the paragraph.
• Option C: QSPR. This is not the correct answer. The third sentence is a complete sentence, so it cannot be the beginning of the paragraph. The first sentence is a complete sentence, so it must be the beginning of the paragraph.
• Option D: SPRQ. This is not the correct answer. The fifth sentence is a complete sentence, so it cannot be the beginning of the paragraph. The first sentence is a complete sentence, so it must be the beginning of the paragraph.