In the following item, passage consists of six sentences. The first and sixth sentence are given in the beginning as `S_1` and `S_6`. The middle four sentences in each have been jumbled up. These are labelled P, Q, R and S. You are required to find out the proper sequence of the four sentences and indicate your answer accordingly on the Answer Sheet.
`S_1` : What soda-water is composed of you may see for yourself if you watch your glass as it stands on the table after you have slaked your first thirst.
`S_6` : 'Carbonic acid' is the old name for it, but it is more correct to name it, when it is out of the water, 'Carbon dioxide'.
P : The liquid is plain water, as you will find out if you are too slow about drinking.
Q : You will see that it is separating into two different things, a.liquid and a gas.
R : The gas is so heavy that you can fairly drink it from the glass, and it has, as you know, a tingle-tangle taste.
S : The other is a heavy, sour and invisible gas that slips up through the water in little bubbles and collects in the empty half of the glass.
The proper sequence should be :

Options

A. QRSP
B. PRQS
C. QPSR
D. RSPQ