In an examination, a student scores 4 marks for every correct answer and loses 1 mark for every wrong answer. If he attempts all 60 questions and secures 150 marks, the no of questions he attempts correctly is :
Choose the correct choice from the following answers.
A) 35
B) 38
C) 40
D) 42
E) 44

Rationale: "explanation : let the number of correct answers be x . number of incorrect answers = ( 60 – x ) . 4 x – ( 60 – x ) = 150 = > 5 x = 210 = > x = 42 answer : d"
Answer: D