Read the following statements and answer the four items that follow :
Five cities P, Q, R, S and T are connected by different modes of transport as follows :
P and Q are connected by boat as well as rail.
S and R are connected by bus and boat.
Q and T are connected by air only.
P and R are connected by boat only.
T and R are connected by rail and bus.
If a person visits each of the places starting from P and gets back to P, which of the following places must he visit twice ?
If a person visits each of the places starting from P and gets back to P, which of the following places must he visit twice ?