The suffixes -ed and -ing are examples of B. Morphemes
Morphemes are the smallest units of meaning in a language. They can be prefixes, roots, or suffixes. Prefixes are attached to the beginning of a word, roots are the core of a word, and suffixes are attached to the end of a word.
The suffixes -ed and -ing are both examples of suffixes. The suffix -ed is used to form past tense verbs, and the suffix -ing is used to form present participle verbs.