Akash, Bisni, Charu, Dev, Elsa, Fiona and Gaurav sat for their high school examination and their scores were as follows:
a. Bisni always scores more than Dev, who always scores more than Fiona.
b. In any examination, if Charu scores the highest, Elsa scores the least, or if Akash scores the highest, Fiona or Gaurav scores the least.
c. No two students get equal scores.
If Fiona and Akash are ranked 4th and 5th, respectively, which of the following can be true?