Option B is correct because the suffix -ful is used in the formation of adjectives indicating 'full of', hence the adjective 'careful' means 'full of care'. Option A is incorrect because firstly, the suffix is used for adverbs and secondly, this word does not exist. Option C is incorrect because the suffix -some is used for adjectives meaning 'characterized by', and because this word does not exist. Option D is incorrect because it is a verb.