To form a coherent sentence from the given fragments, we need to arrange them in a logical sequence. Let's analyze each fragment:
Q: rooftop gardens and vertical farming
P: are becoming more popular among urban residents
R: as people seek sustainable ways
S: to grow food in limited spaces
Examining the fragments, it makes sense to start with Q because "rooftop gardens and vertical farming" introduce the topic or subjects of the sentence.
Next, P logically follows, providing the main action "are becoming more popular among urban residents" related to the subjects.
Then, R comes naturally as it provides the reason "as people seek sustainable ways", explaining why these methods are gaining popularity.
Finally, S completes the sentence with the phrase "to grow food in limited spaces", further detailing the sustainable methods mentioned.
This analysis gives us the sequence: QPRS, forming the sentence:
Rooftop gardens and vertical farming are becoming more popular among urban residents as people seek sustainable ways to grow food in limited spaces.