Which pair of inflectional suffixes signifies "more than"?

The pair of inflectional suffixes that signifies "more than" is represented by the suffix -er. This suffix is commonly used to create comparative forms of adjectives and some adverbs, indicating a higher degree of the quality being described. For example, when comparing two entities, the adjective "tall" becomes "taller" to signify that one entity possesses the quality of being tall to a greater extent than the other.

On the other hand, -est is used for superlative forms, indicating the highest degree among three or more entities, rather than a comparative relationship. The suffix -ed is typically used to form the past tense of verbs, and -ing denotes continuous action. Neither -ed nor -ing provides a comparative meaning, nor do they imply a sense of "more than." Thus, the correct answer is -er, as it serves the specific function of denoting comparative degrees.