In the question given below, there is a sentence of which some parts have been jumbled. Rearrange these parts, which are labeled as P, Q, R, and S, to produce the correct sentence. Choose the proper sequence.
They decided to visit the new museum ________
P: on the way to the park
Q: where they saw an interesting exhibit
R: while they were out for a walk
S: that sparked a lively discussion between them