Answer: Deepak is ranked third or fourth

Explanation:
Vicky always scores more than Priya and Priya always scores more than Ankit. Thus, Vicky's rank is always numerically lower than Priya's and Priya's rank is always numerically lower than Ankit's.
Either of the following two situations take place. If Raman scores the highest, then Tony scores the least or if Sunil scores the highest, then Deepak or Ankit scores the least. Thus, if Raman is ranked 1st, then Tony is ranked 7th and if Sunil is ranked 1st, then either Deepak of Ankit is ranked 7th.

The question states that Sunil is ranked 6th and Ankit is ranked 5th.
Thus, Raman is ranked 1st and Tony is ranked 7th. So, the following situations are possible for ranks 2, 3 and 4.

2 Vicky, 3 Priya, 4 Deepak
or 2 Vicky, 3 Deepak, 4 Priya
or 2 Deepak, 3 Vicky, 4 Priya

Answer: fourth   

Explanation:
If Raman gets the highest, he will be ranked 1st.
Accordingly, Tony will be ranked 7th.
Now, Priya and Ankit are always ranked numerically higher than Vicky.
Hence, Vicky can never be ranked lower than 4th as if he is ranked 5th, then there will not be enough positions to accommodate both Ankit and Priya.

Answer: None of these

Explanation:
The question states that Ankit's rank is 1st. This is not possible because he always scores less than Vicky and Priya.

Answer: Deepak gets more than Vicky

Explanation:
If Sunil's rank is 2nd, then Raman's rank is 1st and Tony's rank is 7th.
Vicky's lowest numerical rank will be 3rd and so he will always get less than Sunil.
Raman is ranked 1st and so Priya will always get less than Raman.
Vicky scores more than Priya is given in the question data. Hence, by eliminating the options, we can conclude that it is possible for Deepak to get more than Vicky.

Answer: Sunil scores the highest

Explanation:
If Vicky's rank is 5th, then Priya's rank is 6th and Ankit's rank is 7th. Hence, Sunil's rank is highest or Sunil scores the highest.