Concept:"At most 5 marks" means scores of 5 or less, so add all frequencies for marks 1 through 5.Explanation:From the frequency distribution, the number of students who scored 5 marks or fewer is:12+1+9+6+3=31Total number of students is 53.Required percentage:5331×100%=58.49%≈58.5%Answer:Option A: 58.5%