A is the correct answer, because they differ in 'rhyme scheme'. An Italian sonnet is divided into an octave (8 lines) and a sestet (6 lines), and the rhyme scheme is: ABBA ABBA (in the octave) and CDE CDE or CDC CDC (in the sestet).
An English sonnet is divided into three quatrains (3*4 lines) and a couplet (2 lines), and the rhyme scheme is: ABAB CDCD EFEF GG.