The correct answer is three quatrains and a couplet.
There are different types of sonnets, the most famous ones being the Italian (Petrarchan) and the English (Shakespearean) sonnets. Shakespearean sonnets, like Italian ones, also have 14 lines, but they are distributed differently. Unlike the Italian sonnet, which consists of an octave (8 lines) and a sestet (6 lines), Shakespearean sonnet contains three quatrains (3 x 4 lines) and a couplet (2 lines) to conclude the poem.