Step 1: Recall the Battle of Colachel.
The Battle of Colachel was fought in 1741 near Colachel in present-day Tamil Nadu (then part of the Travancore kingdom's territory).
Step 2: Identify the ruler.
Marthanda Varma, the Maharaja of Travancore, led his forces to a decisive victory over the Dutch East India Company (VOC). This was one of the rare instances of an Asian power defeating a European force.
Step 3: Eliminate other options.
Dharma Raja and Ravi Varma were different Travancore rulers; Veera Kerala Varma is unrelated to this battle.
\[ \boxed{\text{Marthanda Varma}} \]