Direction: Given below is a highlighted word followed by 4 sentences. You need to understand whether the sentences are using the word correctly or not. Mark the incorrect sentence with the incorrect word usage as your answer.

Relentless

A. The pursuit of excellence in her studies was relentless.

B. The relentless rain caused flooding across the city.

C. The soldier was relentless on his first day of training.

D. Their relentless efforts improved the bilateral relations significantly.