【正确答案】 C

【答案解析】解析：base(on)vt．把……建立在……的基础上(如：One should base one’s opinions on facts．This book is based on a true story．Teaching is an art based on a science．)。develop vt．发展，形成：开发，研制。concentrate(on)vt．集中；聚集；浓缩。