Correct Answer: $\frac{144}{25}$

Solution : The distance covered by the athlete is the circumference of the circular field multiplied by the number of times he runs around it.
The circumference (C) of a circle, $C = 2\pi r$ where r is the radius of the circle.
Given:
r = 7 m
Number of rounds = 8
Substituting these values into the formula,
Total Distance = 8 × 2 × $\frac{22}{7}$ × 7 = 352 m
The time taken by the athlete is 3 minutes 40 seconds = 220 seconds.
$\text{Speed} = \frac{\text{Total Distance}}{\text{Time}} = \frac{352}{220} \, \text{m/s}$
$\text{Speed} = \frac{352}{220} \, \text{m/s} \times \frac{18}{5} \, \text{km/hr} = \frac{144}{25} \, \text{km/hr} $
Hence, the correct answer is $\frac{144}{25}$.