S1 : This weather -vane often tops a church spire, tower or high building.
S6 : they weather-vane can, however give us some indication of other.
P : They are only wind-vanes.
Q : Neither alone can tell us.
R : They are designed to point to direction from which the wind is coming.
S : Just as the barometer only tells us teh pressure of air, the weathe- vane tells us the direction of wind.

Options

A. PQRS
B. PSRQ
C. PRSQ
D. SPQR

Answer

D