(i). Seven students P, Q, R, S,  T, U and V take a series of tests.
(ii). No two students get similar marks.
(iii). V always scores more than P.
(iv). P always scores more than Q.
(v). Each time either R socres the highest and T gets the least, or alternatively S scores the highest and U or Q scores the least. If R gets most, V should be ranked not lower than :

Answer: C. fourth

In terms of scores, we have :
V > P, P > Q  i.e. V > P > Q.
If R scores the highest, we have R > ...... > T,
If S scores the highest, we have S > ...... > Q or S > ...... > U.

Again, if R ranks most, T ranks lowest and occupies seventh place. Since V always rank above P and Q, so in the maximum, P and Q will occupy fifth and sixth places.
Thus, V will not rank lower than fourth.