10) C

The last sentence of the text states that “offenders who received shorter sentences (less than 12 month) formed 24.2% of the cohort, but committed 39% of all offences that led to a conviction in the first year of the follow-up”.

Number of offences in the first year = (43000 ÷ 100) x 185 = 79, 550

39% of 79,550 ≈ 31,000