In both sexes of cockroach, a pair of jointed filamentous...

Correct answer is option (1), because in both sexes of cockroach, $10^{\text{th }}$ segment bears a pair of jointed filamentous structures called anal cerci. Options (2), (3) and (4) are incorrect because $5^{\text{th }}, 8^{\text{th }}$ and $9^{\text{th }}$ segments do not bear such structures. In adult cockroaches only $10^{\text{th }}$ segments are present in abdomen. $11^{\text{th }}$ abdominal segment is absent.