Correct option is C
Explanation-
Retrotransposons are a class of transposable elements that move via an RNA intermediate transcribed into RNA, reverse transcribed into DNA and inserted into a new genomic location. They do not excise from the genome (unlike DNA transposons), but rather copy and paste. There are two broad classes - LTR retrotransposons (e.g., Copia, Gypsy) – have long terminal repeats and Non-LTR retrotransposons (e.g., LINEs, SINEs) – lack LTRs
Option c : Copia element in Drosophila; LINEs as well as SINEs in humans
Copia in Drosophila is a classic LTR retrotransposon. LINEs in humans are autonomous non-LTR retrotransposons. SINEs in humans are non-autonomous retrotransposons, still part of retroelements. This statement is correct because it includes all valid retrotransposons in both organisms
Incorrect options-
Option a: P elements in Drosophila; LINEs but not SINEs in humans
P elements are DNA transposons, not retrotransposons. They move by cut-and-paste via a transposase enzyme and do not involve RNA or reverse transcription. LINEs (especially LINE-1) are autonomous non-LTR retrotransposons. They encode reverse transcriptase and move via RNA intermediates. This option is incorrect to exclude SINEs, because SINEs (like Alu elements) are also retrotransposons. They are non-autonomous but still use the reverse transcriptase of LINEs
Option b : Copia element in Drosophila; SINEs but not LINEs in humans
Copia in Drosophila is LTR retrotransposon which moves via RNA intermediate using reverse transcriptase. SINEs in humans are Non-LTR retrotransposons, non-autonomous and rely on LINE machinery for movement. This statement is incorrect because LINEs are a major class of retrotransposons in humans. Without including LINEs, this option omits a critical retroelement
Option d : P elements in Drosophila; LINEs as well as SINEs in humans
P elements is a DNA transposons, use a cut-and-paste mechanism not retroelements.
Final answer - Correct option is c - Copia element in Drosophila; LINEs as well as SINEs in humans
