Solution:
Duration of time for which a contestant have to speak = 5 minutes (300 Seconds)
Point lost by a contestant for over-speaking that is for more than 5 minutes for each second = 3 points
Point lost by a contestant for speaking less than 5 minutes on each second = 3 points
So, the expression which can determine ,the number of points a contestant loses if she speaks for x seconds.
⇒Number of points a contestant loses if she speaks for x seconds=
For, example if a contestant speaks for 290 seconds,Points lost by contestant = =3 × 10= 30 Points
If a contestant speaks for 305 seconds,Points lost by contestant = =3 × 5= 15 Points
Option (A)= is right choice describing above situation.