The heroic couplet is a pair of

The correct option is Ten-syllable lines that rhyme.

A heroic couplet is a classic poetic form widely used in English literature, particularly during the Neo-Classical period by poets like Alexander Pope and John Dryden.
It is defined by two key characteristics:
1. Syllable count: The lines are written in iambic pentameter. Since an iambic foot consists of one unstressed syllable followed by one stressed syllable (two syllables total) and pentameter means there are five feet per line, each line contains exactly ten syllables.
2. Rhyme: The two consecutive lines of the couplet rhyme with each other, creating a rhyming pair (AA, BB, CC, etc.).