(B) Smart bot
A Smart bot requires coding and works on bigger databases directly.
The source passage distinguishes two types of chatbots: Script-bot (scripted/traditional, rule-based, simpler) and Smart-bot (AI-powered, works with larger databases, requires coding). The question describes characteristics of a Smart bot. Options C and D are not the two types named in the passage; option A (Script bot) is the simpler, non-coding type.