Directions: Refer to the following table and answer the given questions.
1000 candidates have appeared for a job selection process. Their scores in a written test of 300 marks and a personal interview of 100 marks are given in the following table. The entries in the table denote the number of candidates.
If the qualifying marks in the written test is 160 & the qualifying marks for the interview is reduced from 40 to 30, how many candidates would benefit from it?
Correct answer is option 'B'. Can you explain this answer?