O, P, Q, R, S, T and U are seven boxes that are kept one over the other but not necessarily in the same order. Only one box is kept between R and P. Only one box is kept between S and T. Only one box is kept between P and Q. Q is kept at the lowermost position. T is kept immediately above Q. How many boxes are kept between S and Q?
AOne
BThree
CTwo
DFour