In this section, each item consists of six sentences of a passage. The first and sixth sentences are given as SI and S6. The middle four sentences in each have been jumbled up and labelled as P, Q, R and S. You are required to find the proper sequence of the four sentences and mark your response accordingly.

S1: Hans Christian Oersted, one of the leading scientists of the 19th century, played a crucial role in understanding electromagnetism.
P: In 1820 he accidentally discovered that a compass needle get deflected when an electric current passed through a metallic wire placed nearby.
Q: His research later created technologies such as radio, television and fibre optics.
R: The unit of magnetic field strength is named the oersted in his honour.
S: Through this observation, Oersted showed that electricity and magnetism were related phenomena. 
S6: This is how Orested becomes a unit.