Answer: They are a couplet, B.
Step-by-step explanation:
Typically, a couplet comprises of two lines that follow each other, rhyme, and have the same meter.
All the other options are incorrect.
a) is incorrect as, blank verse is a literary term that refers to poetry written in unrhymed but metered lines, almost always iambic pentameter.
c) is incorrect as, a quatrain is a type of stanza, or a complete poem, consisting of four lines.
d) is incorrect as, a sonnet is a type of fourteen-line poem that is structured with 2 quatrains and a stanza of 6 lines.
e) is incorrect as, a tetrameter is a line of four metrical feet.