The question below consist of a set of labelled (P, Q, R, S) sentences. Out of four options given, select the most logical order of the sentences which form a paragraph.

By the early part of 1939 the German dictator Adolf Hitler had become determined to invade and occupy Poland.

P. In a secret protocol of this pact, the Germans and the Soviets agreed that Poland should be divided between them, with the western third of the country going to Germany and the eastern two-thirds being taken over by the U.S.S.R.

Q. Hitler intended to invade Poland anyway, but first he had to neutralize the possibility that the Soviet Union would resist the invasion of its western neighbour.

R. Poland, for its part, had guarantees of French and British military support should it be attacked by Germany.

S. Secret negotiations led on August 23-24 to the signing of the German-Soviet Nonaggression Pact in Moscow.

Having achieved this cynical agreement, the other provisions of which stupefied Europe even without divulgence of the secret protocol, Hitler thought that Germany could attack Poland with no danger of Soviet or British intervention and gave orders for the invasion to start on August 26.