Translation:Is this question easy?
かんたん and やさしい are both adjectives, so they both describe nouns or pronouns. They both mean "easy" or "simple" and are interchangeable most of the time with little or no loss in meaning. The difference is that かんたん is for things that are objectively easy (e.g. a simple task) and やさしい is used for things that are easy in the speaker's opinion (e.g. an easy exam).