Answer: B. Dark/Heart.
Step-by-step explanation:
Slant rhyme refers to the way poets build a rhythm by employing words that sound alike but do not rhyme perfectly. It´s a rhyme in which either the vowels or the consonants of stressed syllables are identical. For example, other possible rhymes for "heart" are:
star, card, guard, mark, park, chart, dart, smart, and many more.